Oraqix

Browse PDR's full list of drug information

Oraqix

Classes

Other Agents for Local Oral Treatment
Topical Local Anesthetics

Administration
Topical Administration

Lidocaine; prilocaine cream is for use on normal, intact skin or genital mucous membranes only.
Avoid contact with eyes or open wounds.
Apply only to the prescribed area and for no longer than instructed. Application to a larger area or for an extended duration may result in increased absorption of lidocaine and prilocaine and, thus, potential adverse reactions.

Cream/Ointment/Lotion Formulations

Cream:
Determine the amount to be applied based on the indication, application area, patients age, and patient weight (pediatric patients).
To measure 1 gram, gently squeeze the cream out of the tube as a narrow strip that is 1.5 inches long and 0.2 inches wide. Use the number of strips that equals your dose. For example, use 2 strips for a 2 grams dose. Then apply the dose as a thick layer at the site of the procedure.
Cover with an occlusive dressing after application. A secondary protective covering of the cream is not necessary for absorption but may be helpful to keep the cream in place. Do not spread out the cream. If a dressing is used, smooth down the dressing edges carefully to ensure it is secure and to avoid leakage.
Watch pediatric patients to make sure that the cream or occlusive dressing is not eaten or put into the eyes.
Length of application dependent upon type and location of the procedure. Mark the time of the application on the dressing.
Prior to the procedure, remove any protective covering, wipe off the cream, and clean the entire area with an antiseptic solution.
Used occlusive dressings should be folded together so that the adhesive edges are together and disposed of out of reach of children and pets.

Other Topical Formulations

Periodontal Gel:
An air bubble upon tilting the Oraqix cartridge should be apparent. Placement of the cartridge in the refrigerator may be needed to regain the liquid state. Do not freeze. Do not use if a precipitant is apparent.
Do not warm the product (e.g., use a dental cartridge warmer). Heat will cause the product to gel.
Use only the supplied blunt-tipped applicator. Do not use any other device or method to apply the liquid. The blunt-tipped applicator is for single-use only. Do not reuse.
Apply to the gingival margin. After 30 seconds, fill the periodontal pockets until gel is visible at the gingival margin. Usually 1 cartridge (1.7 grams) or less is sufficient for one quadrant of dentition.
Reapplication, depending on the required anesthetic effect, should be limited to a total delivered dose of 8.5 grams (5 cartridges) per treatment session. Anesthetic effect is obtained 30 seconds after application. An increased effect is not obtained beyond 30 seconds.
Direct application to the periodontal pockets appears safe, but the efficacy has not been established.

Adverse Reactions
Severe

visual impairment / Early / Incidence not known
arrhythmia exacerbation / Early / Incidence not known
cardiac arrest / Early / Incidence not known
seizures / Delayed / Incidence not known
bradycardia / Rapid / Incidence not known
bronchospasm / Rapid / Incidence not known
angioedema / Rapid / Incidence not known
anaphylactic shock / Rapid / Incidence not known
anaphylactoid reactions / Rapid / Incidence not known
methemoglobinemia / Early / Incidence not known

Moderate

erythema / Early / 21.0-30.0
edema / Delayed / 6.0-10.0
oral ulceration / Delayed / 1.3-1.3
contact dermatitis / Delayed / Incidence not known
blurred vision / Early / Incidence not known
hypotension / Rapid / Incidence not known
hyperacusis / Delayed / Incidence not known

Mild

pallor / Early / 37.0-37.0
application site reaction / Early / 13.0-13.0
pruritus / Rapid / 2.0-2.0
dysgeusia / Early / 2.0-2.0
headache / Early / 2.0-2.0
rash / Early / 0-1.0
fatigue / Early / 1.0-1.0
infection / Delayed / 1.0-1.0
dizziness / Early / 0.3-0.3
arthropathy / Delayed / 0.3-0.3
myalgia / Early / 0.3-0.3
arthralgia / Delayed / 0.3-0.3
purpura / Delayed / Incidence not known
skin hyperpigmentation / Delayed / Incidence not known
vesicular rash / Delayed / Incidence not known
drowsiness / Early / Incidence not known
tremor / Early / Incidence not known
urticaria / Rapid / Incidence not known
nausea / Early / Incidence not known

Common Brand Names

ANODYNE LPT, Aprizio Pak II, DermacinRx, DermacinRx Empricaine, DermacinRx Prizopak, Dolotranz, EMLA, Empricaine-II, IV Novice Pack, Leva Set, Lido-Prilo Caine, Lidotor, LiProZonePak, LIVIXIL Pak, LP Lite Pak, Medolor Pak with Tegaderm Dressing, Microvix LP, Nuvakaan, Nuvakaan-II, Oraqix, Port-Prep, PrepIV, PRILOHEAL PLUS 30, Prilovix, Prilovix Lite, Prilovix Lite Plus, Prilovix Plus, Prilovix Ultralite, Prilovix Ultralite Plus, Prilovixil, Prizopak-II, REAL HEAL-I, Relador, Soluline, SOLUPICC, VallaDerm-90

Dea Class

Rx

Description

Lidocaine 2.5% and prilocaine 2.5% used for topical and dental anesthesia
Available as a cream and periodontal gel
Cases of methemoglobinemia have been reported in association with lidocaine; prilocaine use; monitoring for signs and symptoms of methemoglobinemia is recommended

Dosage And Indications
For use as local anesthesia to provide topical anesthesia. Application to intact skin prior to minor dermal procedures (e.g., intravenous cannulation and venipuncture). Topical dosage (cream or disc) Adults, Adolescents, and Children

Apply 2.5 g of EMLA cream over 20—25 cm2 of skin surface or 1 disc (1 g over 10 cm2) for at least 1 hour. Cover cream with an occlusive dressing. Dermal analgesia can be expected to increase for up to 3 hours under occlusive dressing and persist for 1—2 hours after removal of the cream. The maximum recommended duration of exposure is 4 hours.

Infants 4—12 months weighing 5—10 kg

Apply 1 disc (1 g over 10 cm2) or no more than 2 g EMLA cream over a maximum 20 cm2 surface area at least 1 hour before the procedure. Cover cream with an occlusive dressing.

Neonates >= 37 weeks gestation and Infants 1—3 months or weighing < 5 kg

Apply 1 disc (1 g over 10 cm2) or no more than 1 g of cream to a maximum 10 cm2 surface area at least 1 hour before the procedure. Cover cream with an occlusive dressing.

Application to intact skin for major dermal procedures (e.g., split thickness skin graft harvesting). Topical dosage (cream) Adults, Adolescents, and Children > 10 kg

Apply 2 g of EMLA cream per 10 cm2 of skin. The cream should be covered with an occlusive dressing and remain in contact with the skin for at least 2 hours.

Children and Infants 4—12 months weighing 5—10 kg

Apply no more than 2 g EMLA cream over a maximum 20 cm2 surface area at least 2 hours before the procedure. Cover cream with an occlusive dressing.

Neonates >= 37 weeks gestation and Infants 1—3 months or weighing < 5 kg

Apply no more than 1 g of EMLA cream to a maximum 10 cm2 surface area at least 2 hours before the procedure. Cover cream with an occlusive dressing.

Application to male genital mucous membranes as a pretreatment to local anesthetic infiltration. Topical dosage (cream) Male Adults, Adolescents, Children, Infants, and Neonates >= 37 weeks gestation

Apply a thick layer of EMLA cream (1 g/10 cm2) to skin surface for 15 minutes. Cover cream with an occlusive dressing. Local anesthetic infiltration should begin immediately after removal of EMLA cream.

Application to adult female external genitalia prior to minor procedures (e.g., removal of condylomata acuminata) or prior to infiltration anesthesia. Topical dosage (cream) Adult and Adolescent † females

Apply a thick layer (5—10 g) of EMLA cream for 5—10 minutes. Occlusion is not necessary for absorption but may be helpful to keep the cream in place. Patients should be lying down during application of the cream, especially if no occlusion is used. The procedure or local anesthetic infiltration should begin immediately after removal of the cream.

Application to periodontal pockets during scaling and/or root planing. Topical dosage (Oraqix periodontal gel) Adults

Apply the liquid to the gingival margin; after 30 seconds, fill the periodontal pockets until the gel is visible at the gingival margin. Maximum anesthetic effect is obtained 30 seconds after application. Reapplication is appropriate if the anesthetic effect begins to wane.

Application to intact skin prior to subcutaneous or intramuscular vaccine receipt†. Topical dosage (disc) Children and Infants

1 disc (1 g over 10 cm2) applied 1 hour before SC receipt of the MMR vaccine to children at least 1 year of age or before IM receipt of diphtheria-tetanus-acellular pertussis-inactivated poliovirus -Haemophilus influenzae type b conjugate and hepatitis B vaccines to infants resulted in significantly less pain as compared with children that received a placebo patch. Cry, facial expression, and body movement were assessed by use of the Modified Behavioral Pain Scale immediately before and for 2 minutes after vaccine receipt.

For the treatment of premature ejaculation†. Topical dosage Adult males

Lidocaine; prilocaine (2.5%-2.5%) applied 20 to 30 minutes before intercourse has been shown to increase ejaculatory latency and is suggested per treatment guidelines. Topical anesthetic is applied to the penis before intercourse. A condom may or may not be used; the condom may be removed before sexual intercourse and the penis washed clean of any residual anesthetic. Prolonged application (beyond 20 minutes) may be associated with loss of erection due to numbness; direct contact of the anesthetic to the vaginal wall may also result in numbness to the partner.

†Indicates off-label use

Dosing Considerations
Hepatic Impairment

Specific dosing guidelines are not available. The half-lives of prilocaine and lidocaine may be increased in patients with hepatic impairment. Patients with severe hepatic disease, because of their inability to metabolize local anesthetics normally, are at greater risk of developing toxic plasma concentrations of lidocaine and prilocaine.

Renal Impairment

Specific dosing guidelines are not available. The half-life of prilocaine may be prolonged in patients with renal impairment. Metabolites of lidocaine and prilocaine may accumulate in patients with renal dysfunction.

Drug Interactions

Acebutolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Acetaminophen: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Aspirin, ASA; Caffeine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Aspirin: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Aspirin; Diphenhydramine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Caffeine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Caffeine; Dihydrocodeine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Acetaminophen; Caffeine; Pyrilamine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Chlorpheniramine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Chlorpheniramine; Dextromethorphan: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Chlorpheniramine; Phenylephrine : (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Codeine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Acetaminophen; Dextromethorphan: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Dextromethorphan; Doxylamine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Dextromethorphan; Guaifenesin; Phenylephrine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Dextromethorphan; Guaifenesin; Pseudoephedrine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Dextromethorphan; Phenylephrine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Dextromethorphan; Pseudoephedrine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Dichloralphenazone; Isometheptene: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Diphenhydramine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Guaifenesin; Phenylephrine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Hydrocodone: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Acetaminophen; Ibuprofen: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Oxycodone: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Acetaminophen; Pamabrom; Pyrilamine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Phenylephrine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acetaminophen; Pseudoephedrine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Acyclovir: (Moderate) Monitor for lidocaine toxicity if coadministration with acyclovir is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP1A2 substrate and acyclovir is a CYP1A2 inhibitor. Coadministration of another CYP1A2 inhibitor increased lidocaine exposure by 71%.
Adagrasib: (Moderate) Monitor for lidocaine toxicity if coadministration with adagrasib is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and adagrasib is a strong CYP3A inhibitor.
Adapalene; Benzoyl Peroxide: (Moderate) Concurrent use of benzoyl peroxide and topical anesthetics may decrease the efficacy of the anesthetic. In a clinical study, an estimated 75% increase in patient-reported, prick-induced pain was noted in areas treated with both 5% benzoyl peroxide and 6% benzocaine cream as compared to areas treated with 6% benzocaine cream alone. Investigators attributed the decreased anesthetic effect to a breakdown of the benzocaine molecule by either or both benzoyl peroxide or benzoyl peroxide-derived free radicals. It is recommended that the skin area that is to be topically anesthetized have no previous treatment with benzoyl peroxide or that the skin is thoroughly washed prior to the application of the anesthetic.
Aldesleukin, IL-2: (Moderate) Concomitant use of systemic lidocaine and aldesleukin may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; aldesleukin inhibits CYP3A4.
Alfentanil: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Aminosalicylate sodium, Aminosalicylic acid: (Moderate) Coadministration of lidocaine with oxidizing agents, such as aminosalicylic acid, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as aminosalicylic acid, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Amiodarone: (Major) Concomitant administration of lidocaine with amiodarone has been reported to cause sinus bradycardia and seizure. Amiodarone and its main metabolite, N-monodesethylamiodarone (DEA), appear to inhibit the metabolism of lidocaine by competitively inhibiting CYP3A4. Furthermore, DEA inhibits lidocaine metabolism in a concentration-dependent manner. Also, the metabolism of amiodarone to DEA appears to be competitively inhibited by lidocaine. Close correlations between amiodarone N-monodesethylase activities and the amounts of CYP3A4 and the rates of lidocaine N-monodesethylation have been observed from analyses of in vitro data. Inhibition of lidocaine metabolism is supported by in vivo data from 6 adults. The mean systemic concentration of lidocaine over 300 minutes after receipt of lidocaine hydrochloride 1 mg/kg intravenously before amiodarone treatment is 111.7 +/- 23.2 mcg/minute/mL. In contrast, the mean systemic concentration of lidocaine over 300 minutes after cumulative amiodarone doses of 3 g and 13 g is 135.3 +/- 34.6 and 131.7 +/- 25.5 mcg/minute/mL, respectively. As expected, the systemic exposure of the lidocaine metabolite, monoethylglycinexylidide, decreases from 19.2 +/- 6.5 to 15.8 +/- 8.3 mcg/minute/mL after 3 g of amiodarone. In addition, the systemic clearance of lidocaine decreases from 7.86 +/- 1.83 to 6.31 +/- 2.21 mL/minute/kg body weight. As compared with values before amiodarone administration, the lidocaine elimination half-life and the distribution volume at steady state remain relatively unchanged. Due to the long half-life of amiodarone, clinicians should use caution when administering lidocaine to patients who are receiving or who have recently discontinued amiodarone.
Amitriptyline: (Major) If epinephrine is added to lidocaine for the purpose of infiltration and nerve block or spinal anesthesia, receipt of the product to a patient taking tricyclic antidepressants (TCA) may lead to severe, prolonged hypertension. In general, concurrent use of a local anesthetic solution containing epinephrine and a TCA should be avoided. If coadministration is necessary, careful patient monitoring is essential. (Major) Use prilocaine and tricyclic antidepressants together with caution. If epinephrine is added to prilocaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Administration of a phenothiazine or a butyrophenone may reduce or reverse the pressor effect of epinephrine.
Amlodipine: (Moderate) Concomitant use of systemic lidocaine and amlodipine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; amlodipine inhibits CYP3A4.
Amlodipine; Atorvastatin: (Moderate) Concomitant use of systemic lidocaine and amlodipine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; amlodipine inhibits CYP3A4.
Amlodipine; Benazepril: (Moderate) Concomitant use of systemic lidocaine and amlodipine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; amlodipine inhibits CYP3A4.
Amlodipine; Celecoxib: (Moderate) Concomitant use of systemic lidocaine and amlodipine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; amlodipine inhibits CYP3A4.
Amlodipine; Olmesartan: (Moderate) Concomitant use of systemic lidocaine and amlodipine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; amlodipine inhibits CYP3A4.
Amlodipine; Valsartan: (Moderate) Concomitant use of systemic lidocaine and amlodipine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; amlodipine inhibits CYP3A4.
Amlodipine; Valsartan; Hydrochlorothiazide, HCTZ: (Moderate) Concomitant use of systemic lidocaine and amlodipine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; amlodipine inhibits CYP3A4.
Amoxicillin; Clarithromycin; Omeprazole: (Moderate) Concomitant use of systemic lidocaine and clarithromycin may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; clarithromycin inhibits CYP3A4.
Anagrelide: (Moderate) Anagrelide has been shown to inhibit CYP1A2. In theory, coadministration of anagrelide with substrates of CYP1A2, including lidocaine, could lead to increases in the serum concentrations of lidocaine and, thus, adverse effects. Patients receiving anagrelide and lidocaine concomitantly should be monitored for increased toxicity of lidocaine.
Apalutamide: (Moderate) Monitor for decreased efficacy of lidocaine if coadministration of systemic lidocaine with apalutamide is necessary; higher doses of lidocaine may be required. Lidocaine is a CYP3A4 substrate and apalutamide is a strong CYP3A4 inducer.
Aprepitant, Fosaprepitant: (Major) Use caution if lidocaine and aprepitant, fosaprepitant are used concurrently and monitor for an increase in lidocaine-related adverse effects, including QT prolongation and torsade de pointes (TdP), for several days after administration of a multi-day aprepitant regimen. This interaction is not expected with topical preparations of lidocaine. Lidocaine is a CYP3A4 substrate. Aprepitant, when administered as a 3-day oral regimen (125 mg/80 mg/80 mg), is a moderate CYP3A4 inhibitor and inducer and may increase plasma concentrations of systemic lidocaine. For example, a 5-day oral aprepitant regimen increased the AUC of another CYP3A4 substrate, midazolam (single dose), by 2.3-fold on day 1 and by 3.3-fold on day 5. After a 3-day oral aprepitant regimen, the AUC of midazolam (given on days 1, 4, 8, and 15) increased by 25% on day 4, and then decreased by 19% and 4% on days 8 and 15, respectively. As a single 125 mg or 40 mg oral dose, the inhibitory effect of aprepitant on CYP3A4 is weak, with the AUC of midazolam increased by 1.5-fold and 1.2-fold, respectively. After administration, fosaprepitant is rapidly converted to aprepitant and shares many of the same drug interactions. However, as a single 150 mg intravenous dose, fosaprepitant only weakly inhibits CYP3A4 for a duration of 2 days; there is no evidence of CYP3A4 induction. Fosaprepitant 150 mg IV as a single dose increased the AUC of midazolam (given on days 1 and 4) by approximately 1.8-fold on day 1; there was no effect on day 4. Less than a 2-fold increase in the midazolam AUC is not considered clinically important.
Articaine; Epinephrine: (Moderate) Monitor patients who receive epinephrine while concomitantly taking antiarrhythmics for the development of arrhythmias. Epinephrine may produce ventricular arrhythmias in patients who are on drugs that may sensitize the heart to arrhythmias. (Moderate) Use articaine and lidocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Use articaine and prilocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Asciminib: (Moderate) Monitor for lidocaine toxicity if coadministration with asciminib is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and asciminib is a weak CYP3A inhibitor.
Aspirin, ASA; Carisoprodol; Codeine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Aspirin, ASA; Oxycodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Atazanavir: (Moderate) Anti-retroviral protease inhibitors can inhibit hepatic cytochrome P450 3A4, an isoenzyme that is partially responsible for the metabolism of lidocaine. The concurrent use of systemic lidocaine and anti-retroviral protease inhibitors should be carefully monitored due to the potential for serious toxicity. (Moderate) Atazanavir inhibits the CYP3A4 isoenzyme at clinically relevant concentrations, which may lead to increased serum concentrations of local anesthetics and an increased potential for QT prolongation or other adverse effects.
Atazanavir; Cobicistat: (Moderate) Anti-retroviral protease inhibitors can inhibit hepatic cytochrome P450 3A4, an isoenzyme that is partially responsible for the metabolism of lidocaine. The concurrent use of systemic lidocaine and anti-retroviral protease inhibitors should be carefully monitored due to the potential for serious toxicity. (Moderate) Atazanavir inhibits the CYP3A4 isoenzyme at clinically relevant concentrations, which may lead to increased serum concentrations of local anesthetics and an increased potential for QT prolongation or other adverse effects. (Moderate) Monitor for lidocaine-related adverse reactions if coadministration with cobicistat is necessary. Lidocaine is a CYP3A4 substrate and cobicistat is a strong CYP3A4 inhibitor.
Atenolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Atenolol; Chlorthalidone: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Atracurium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
Avacopan: (Moderate) Monitor for lidocaine toxicity if coadministration with avacopan is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and avacopan is a weak CYP3A inhibitor.
Belladonna; Opium: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Belumosudil: (Moderate) Monitor for lidocaine toxicity if coadministration with belumosudil is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and belumosudil is a weak CYP3A inhibitor.
Benzalkonium Chloride; Benzocaine: (Moderate) Caution is advised if combining topical local anesthetics. The toxic effects of local anesthetics are additive. In addition, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. (Moderate) Use lidocaine and benzocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Benzhydrocodone; Acetaminophen: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Benzocaine: (Moderate) Caution is advised if combining topical local anesthetics. The toxic effects of local anesthetics are additive. In addition, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. (Moderate) Use lidocaine and benzocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Benzocaine; Butamben; Tetracaine: (Moderate) Caution is advised if combining topical local anesthetics. The toxic effects of local anesthetics are additive. In addition, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. (Moderate) Use lidocaine and benzocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Benzoyl Peroxide: (Moderate) Concurrent use of benzoyl peroxide and topical anesthetics may decrease the efficacy of the anesthetic. In a clinical study, an estimated 75% increase in patient-reported, prick-induced pain was noted in areas treated with both 5% benzoyl peroxide and 6% benzocaine cream as compared to areas treated with 6% benzocaine cream alone. Investigators attributed the decreased anesthetic effect to a breakdown of the benzocaine molecule by either or both benzoyl peroxide or benzoyl peroxide-derived free radicals. It is recommended that the skin area that is to be topically anesthetized have no previous treatment with benzoyl peroxide or that the skin is thoroughly washed prior to the application of the anesthetic.
Benzoyl Peroxide; Clindamycin: (Moderate) Concurrent use of benzoyl peroxide and topical anesthetics may decrease the efficacy of the anesthetic. In a clinical study, an estimated 75% increase in patient-reported, prick-induced pain was noted in areas treated with both 5% benzoyl peroxide and 6% benzocaine cream as compared to areas treated with 6% benzocaine cream alone. Investigators attributed the decreased anesthetic effect to a breakdown of the benzocaine molecule by either or both benzoyl peroxide or benzoyl peroxide-derived free radicals. It is recommended that the skin area that is to be topically anesthetized have no previous treatment with benzoyl peroxide or that the skin is thoroughly washed prior to the application of the anesthetic.
Benzoyl Peroxide; Erythromycin: (Moderate) Concurrent us

e of benzoyl peroxide and topical anesthetics may decrease the efficacy of the anesthetic. In a clinical study, an estimated 75% increase in patient-reported, prick-induced pain was noted in areas treated with both 5% benzoyl peroxide and 6% benzocaine cream as compared to areas treated with 6% benzocaine cream alone. Investigators attributed the decreased anesthetic effect to a breakdown of the benzocaine molecule by either or both benzoyl peroxide or benzoyl peroxide-derived free radicals. It is recommended that the skin area that is to be topically anesthetized have no previous treatment with benzoyl peroxide or that the skin is thoroughly washed prior to the application of the anesthetic.
Benzoyl Peroxide; Sulfur: (Moderate) Concurrent use of benzoyl peroxide and topical anesthetics may decrease the efficacy of the anesthetic. In a clinical study, an estimated 75% increase in patient-reported, prick-induced pain was noted in areas treated with both 5% benzoyl peroxide and 6% benzocaine cream as compared to areas treated with 6% benzocaine cream alone. Investigators attributed the decreased anesthetic effect to a breakdown of the benzocaine molecule by either or both benzoyl peroxide or benzoyl peroxide-derived free radicals. It is recommended that the skin area that is to be topically anesthetized have no previous treatment with benzoyl peroxide or that the skin is thoroughly washed prior to the application of the anesthetic.
Berotralstat: (Moderate) Monitor for lidocaine toxicity if coadministration with berotralstat is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A4 substrate and berotralstat is a moderate CYP3A4 inhibitor.
Beta-adrenergic blockers: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Betaxolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Bexarotene: (Moderate) Concomitant use of systemic lidocaine and bexarotene may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; bexarotene induces CYP3A4.
Bicalutamide: (Moderate) Monitor for lidocaine toxicity if coadministration with bicalutamide is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A4 substrate and bicalutamide is a weak CYP3A4 inhibitor.
Bisoprolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Bisoprolol; Hydrochlorothiazide, HCTZ: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Brimonidine; Timolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Bupivacaine Liposomal: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Liposomal bupivacaine administration may follow lidocaine administration after a delay of 20 minutes or more. Use lidocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use prilocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Bupivacaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Liposomal bupivacaine administration may follow lidocaine administration after a delay of 20 minutes or more. Use lidocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use prilocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Bupivacaine; Epinephrine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Liposomal bupivacaine administration may follow lidocaine administration after a delay of 20 minutes or more. Use lidocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use prilocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Monitor patients who receive epinephrine while concomitantly taking antiarrhythmics for the development of arrhythmias. Epinephrine may produce ventricular arrhythmias in patients who are on drugs that may sensitize the heart to arrhythmias.
Bupivacaine; Lidocaine: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Liposomal bupivacaine administration may follow lidocaine administration after a delay of 20 minutes or more. Use lidocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use prilocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Bupivacaine; Meloxicam: (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Liposomal bupivacaine administration may follow lidocaine administration after a delay of 20 minutes or more. Use lidocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Major) Avoid use of other local anesthetics for 96 hours after liposomal bupivacaine administration. Use prilocaine and other formulations of bupivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Butalbital; Acetaminophen: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Butalbital; Acetaminophen; Caffeine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Butalbital; Acetaminophen; Caffeine; Codeine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Butalbital; Aspirin; Caffeine; Codeine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Calamine; Pramoxine: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Calcium Carbonate; Famotidine; Magnesium Hydroxide: (Moderate) Concomitant use of systemic lidocaine and famotidine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; famotidine inhibits CYP1A2.
Cannabidiol: (Moderate) Monitor for lidocaine toxicity if coadministration with cannabidiol is necessary as concurrent use may increase lidocaine exposure. Consider a dose reduction of lidocaine as clinically appropriate, if adverse reactions occur when administered with cannabidiol. Lidocaine is a CYP1A2 substrate and cannabidiol is a weak CYP1A2 inhibitor. Coadministration of another CYP1A2 inhibitor increased lidocaine exposure by 71%.
Capmatinib: (Moderate) Monitor for lidocaine toxicity if coadministration with capmatinib is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP1A2 substrate and capmatinib is a CYP1A2 inhibitor. Coadministration of another CYP1A2 inhibitor increased lidocaine exposure by 71%.
Capreomycin: (Moderate) Partial neuromuscular blockade has been reported with capreomycin after the administration of large intravenous doses or rapid intravenous infusion. Lidocaine could potentiate the neuromuscular blocking effect of capreomycin by impairing transmission of impulses at the motor nerve terminals. If these drugs are used in combination, monitor patients for increased adverse effects.
Carbamazepine: (Moderate) Concomitant use of systemic lidocaine and carbamazepine may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; carbamazepine induces both hepatic isoenzymes.
Carteolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Carvedilol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Ceritinib: (Moderate) Monitor for lidocaine toxicity if coadministration with ceritinib is necessary. Ceritinib is a strong CYP3A4 inhibitor; lidocaine is metabolized by CYP3A4 and CYP1A2. Concomitant treatment CYP3A4 inhibitors has the potential to increase lidocaine plasma levels by decreasing lidocaine clearance and prolonging the elimination half-life.
Chloramphenicol: (Moderate) Concomitant use of systemic lidocaine and chloramphenicol may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; chloramphenicol inhibits CYP3A4.
Chlordiazepoxide; Amitriptyline: (Major) If epinephrine is added to lidocaine for the purpose of infiltration and nerve block or spinal anesthesia, receipt of the product to a patient taking tricyclic antidepressants (TCA) may lead to severe, prolonged hypertension. In general, concurrent use of a local anesthetic solution containing epinephrine and a TCA should be avoided. If coadministration is necessary, careful patient monitoring is essential. (Major) Use prilocaine and tricyclic antidepressants together with caution. If epinephrine is added to prilocaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Administration of a phenothiazine or a butyrophenone may reduce or reverse the pressor effect of epinephrine.
Chloroprocaine: (Moderate) Use lidocaine and chloroprocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Use prilocaine and chloroprocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Chloroquine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as chloroquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as chloroquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Chloroxylenol; Hydrocortisone; Pramoxine: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Chlorpheniramine; Codeine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Chlorpheniramine; Dihydrocodeine; Phenylephrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Chlorpheniramine; Hydrocodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Cholinesterase inhibitors: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary. (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used; dosage adjustments of the cholinesterase inhibitor may be necessary. In addition, inhibitors of CYP1A2, such as tacrine, could theoretically reduce lidocaine metabolism and increase the risk of toxicity when given concurrently. Also, rivastigmine is an acetylcholinesterase inhibitor and therefore is likely to exaggerate muscle relaxation under general anesthetics.
Cimetidine: (Moderate) Concomitant use of systemic lidocaine and cimetidine may increase lidocaine plasma concentrations. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP1A2 and CYP3A4 substrate; cimetidine inhibits both of these isoenzymes. Concomitant use of lidocaine with a weak CYP1A2 and CYP3A4 inhibitor has reportedly increased lidocaine plasma concentrations by 24% to 75%.
Ciprofloxacin: (Moderate) Concomitant use of systemic lidocaine and ciprofloxacin may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; ciprofloxacin inhibits both of these isoenzymes. In a study of healthy volunteers (n = 9), concomitant use of lidocaine (1.5mg/kg IV) and ciprofloxacin (500 mg twice daily) resulted in an increase of lidocaine Cmax and AUC by 12% and 26%, respectively.
Cisatracurium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
Clarithromycin: (Moderate) Concomitant use of systemic lidocaine and clarithromycin may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; clarithromycin inhibits CYP3A4.
Clomipramine: (Major) If epinephrine is added to lidocaine for the purpose of infiltration and nerve block or spinal anesthesia, receipt of the product to a patient taking tricyclic antidepressants (TCA) may lead to severe, prolonged hypertension. In general, concurrent use of a local anesthetic solution containing epinephrine and a TCA should be avoided. If coadministration is necessary, careful patient monitoring is essential. (Major) Use prilocaine and tricyclic antidepressants together with caution. If epinephrine is added to prilocaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Administration of a phenothiazine or a butyrophenone may reduce or reverse the pressor effect of epinephrine.
Cobicistat: (Moderate) Monitor for lidocaine-related adverse reactions if coadministration with cobicistat is necessary. Lidocaine is a CYP3A4 substrate and cobicistat is a strong CYP3A4 inhibitor.
Codeine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Codeine; Guaifenesin: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Codeine; Guaifenesin; Pseudoephedrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Codeine; Phenylephrine; Promethazine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Codeine; Promethazine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Colesevelam: (Moderate) Colesevelam may decrease the absorption of lidocaine. To minimize potential for interactions, consider administering lidocaine at least 1 hour before or at least 4 hours after colesevelam.
Colistin: (Moderate) Lidocaine can potentiate the neuromuscular blocking effect of colistimethate sodium by impairing transmission of impulses at the motor nerve terminals. If these drugs are used in combination, monitor patients for increased adverse effects. Neuromuscular blockade may be associated with colistimethate sodium, and is more likely to occur in patients with renal dysfunction.
Conivaptan: (Moderate) Monitor for lidocaine toxicity if coadministration with conivaptan is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and conivaptan is a moderate CYP3A inhibitor.
Crizotinib: (Moderate) Monitor for lidocaine-related adverse reactions and toxicities if coadministration with crizotinib is necessary. Lidocaine is a CYP3A4 substrate and crizotinib is a moderate CYP3A inhibitor.
Cyclophosphamide: (Moderate) Coadministration of lidocaine with oxidizing agents, such as cyclophosphamide, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as cyclophosphamide, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Cyclosporine: (Moderate) Concomitant use of systemic lidocaine and cyclosporine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; cyclosporine inhibits CYP3A4.
Dabrafenib: (Moderate) Concomitant use of systemic lidocaine and dabrafenib may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; dabrafenib induces CYP3A4.
Dalfopristin; Quinupristin: (Moderate) Coadministration of lidocaine with dalfopristin; quinupristin may result in elevated lidocaine plasma concentrations. If these drugs are used together, closely monitor for signs of lidocaine-related adverse events. Lidocaine is a substrate of CYP3A; dalfopristin; quinupristin is a weak CYP3A inhibitor.
Danazol: (Moderate) Danazol is a CYP3A4 inhibitor and may decrease the hepatic metabolism of lidocaine. Patients receiving lidocaine should be closely monitored for toxicity if danazol is added to therapy.
Dapsone: (Moderate) Coadministration of dapsone with lidocaine may increase the risk of developing methemoglobinemia. Advise patients to discontinue treatment and seek immediate medical attention with any signs or symptoms of methemoglobinemia. (Moderate) Coadministration of dapsone with prilocaine may increase the risk of developing methemoglobinemia. Advise patients to discontinue treatment and seek immediate medical attention with any signs or symptoms of methemoglobinemia.
Daratumumab; Hyaluronidase: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
Darunavir: (Major) Darunavir can inhibit CYP3A4, an isoenzyme partially responsible for the metabolism of lidocaine. The concurrent use of systemic lidocaine and darunavir should be carefully monitored due to the potential for serious toxicity.
Darunavir; Cobicistat: (Major) Darunavir can inhibit CYP3A4, an isoenzyme partially responsible for the metabolism of lidocaine. The concurrent use of systemic lidocaine and darunavir should be carefully monitored due to the potential for serious toxicity. (Moderate) Monitor for lidocaine-related adverse reactions if coadministration with cobicistat is necessary. Lidocaine is a CYP3A4 substrate and cobicistat is a strong CYP3A4 inhibitor.
Darunavir; Cobicistat; Emtricitabine; Tenofovir alafenamide: (Major) Darunavir can inhibit CYP3A4, an isoenzyme partially responsible for the metabolism of lidocaine. The concurrent use of systemic lidocaine and darunavir should be carefully monitored due to the potential for serious toxicity. (Moderate) Monitor for lidocaine-related adverse reactions if coadministration with cobicistat is necessary. Lidocaine is a CYP3A4 substrate and cobicistat is a strong CYP3A4 inhibitor.
Deferasirox: (Major) Concomitant use of systemic lidocaine and deferasirox may alter lidocaine plasma concentrations; avoid concurrent use. If use together is necessary, monitor patients closely for lidocaine toxicity and therapeutic efficacy. Lidocaine is a CYP3A4 and CYP1A2 substrate; deferasirox inhibits CYP1A2 and induces CYP3A4.
Delavirdine: (Moderate) Delavirdine is a potent inhibitor of the CYP3A4 and increased plasma concentrations of drugs extensively metabolized by this enzyme, such as lidocaine, should be expected with concurrent use of delavirdine.
Desipramine: (Major) If epinephrine is added to lidocaine for the purpose of infiltration and nerve block or spinal anesthesia, receipt of the product to a patient taking tricyclic antidepressants (TCA) may lead to severe, prolonged hypertension. In general, concurrent use of a local anesthetic solution containing epinephrine and a TCA should be avoided. If coadministration is necessary, careful patient monitoring is essential. (Major) Use prilocaine and tricyclic antidepressants together with caution. If epinephrine is added to prilocaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Administration of a phenothiazine or a butyrophenone may reduce or reverse the pressor effect of epinephrine.
Dextromethorphan; Quinidine: (Major) Avoid concurrent use of quinidine with other antiarrhythmics with Class I activities, such as lidocaine. Concurrent use may result in additive or antagonistic cardiac effects and additive toxicity.
Dibucaine: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Diltiazem: (Moderate) Concomitant use of systemic lidocaine and diltiazem may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; diltiazem inhibits CYP3A4.
Disopyramide: (Major) The effects of concomitant administration of disopyramide with other antiarrhythmics could potentially be synergistic or antagonistic, and adverse cardiac effects could potentially be additive. Class IA antiarrhythmic agents are associated with proarrhythmias (e.g., torsades de pointes) resulting from QTc prolongation. Coadministration of disopyramide with other Class IA antiarrhythmics should be reserved for patients with life-threatening arrhythmias who are unresponsive to single-agent antiarrhythmic therapy. Lidocaine has occasionally been used concurrently with disopyramide; however, additive electrophysiologic effects may occur. Since disopyramide and lidocaine are both sodium-channel-acting agents, it is somewhat irrational to use these drugs together; isolated cases of intraventricular conduction abnormalities have been reported with this drug combination. Patients receiving more than one antiarrhythmic drug must be carefully monitored.
Disulfiram: (Moderate) Concomitant use of systemic lidocaine and disulfiram may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; disulfiram inhibits CYP1A2.
Dofetilide: (Contraindicated) Concurrent exposure of systemic lidocaine with dofetilide could increase the risk of dofetilide-induced proarrhythmias. Before switching from lidocaine to dofetilide therapy, lidocaine generally should be withheld for at least three half-lives prior to initiating dofetilide. Dofetilide, a Class III antiarrhythmic agent, is associated with a well-established risk of QT prolongation and torsades de pointes (TdP).
Donepezil: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary. (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used; dosage adjustments of the cholinesterase inhibitor may be necessary. In addition, inhibitors of CYP1A2, such as tacrine, could theoretically reduce lidocaine metabolism and increase the risk of toxicity when given concurrently. Also, rivastigmine is an acetylcholinesterase inhibitor and therefore is likely to exaggerate muscle relaxation under general anesthetics.
Donepezil; Memantine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary. (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used; dosage adjustments of the cholinesterase inhibitor may be necessary. In addition, inhibitors of CYP1A2, such as tacrine, could theoretically reduce lidocaine metabolism and increase the risk of toxicity when given concurrently. Also, rivastigmine is an acetylcholinesterase inhibitor and therefore is likely to exaggerate muscle relaxation under general anesthetics.
Dorzolamide; Timolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Doxepin: (Major) If epinephrine is added to lidocaine for the purpose of infiltration and nerve block or spinal anesthesia, receipt of the product to a patient taking tricyclic antidepressants (TCA) may lead to severe, prolonged hypertension. In general, concurrent use of a local anesthetic solution containing epinephrine and a TCA should be avoided. If coadministration is necessary, careful patient monitoring is essential. (Major) Use prilocaine and tricyclic antidepressants together with caution. If epinephrine is added to prilocaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Administration of a phenothiazine or a butyrophenone may reduce or reverse the pressor effect of epinephrine.
Dronedarone: (Moderate) Concomitant use of systemic lidocaine and dronedarone may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; dronedarone inhibits CYP3A4.
Efavirenz: (Moderate) Efavirenz induces cytochrome P450 (CYP) 3A4 and thus, may decrease serum concentrations of lidocaine. Caution is recommended when administering efavirenz with CYP3A4 substrates that have a narrow therapeutic range (e.g., systemic lidocaine).
Efavirenz; Emtricitabine; Tenofovir Disoproxil Fumarate: (Moderate) Efavirenz induces cytochrome P450 (CYP) 3A4 and thus, may decrease serum concentrations of lidocaine. Caution is recommended when administering efavirenz with CYP3A4 substrates that have a narrow therapeutic range (e.g., systemic lidocaine).
Efavirenz; Lamivudine; Tenofovir Disoproxil Fumarate: (Moderate) Efavirenz induces cytochrome P450 (CYP) 3A4 and thus, may decrease serum concentrations of lidocaine. Caution is recommended when administering efavirenz with CYP3A4 substrates that have a narrow therapeutic range (e.g., systemic lidocaine).
Efgartigimod Alfa; Hyaluronidase: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
Elagolix: (Moderate) Concomitant use of systemic lidocaine and elagolix may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; elagolix is a weak to moderate CYP3A4 inducer.
Elagolix; Estradiol; Norethindrone acetate: (Moderate) Concomitant use of systemic lidocaine and elagolix may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; elagolix is a weak to moderate CYP3A4 inducer.
Elbasvir; Grazoprevir: (Moderate) Administering lidocaine with elbasvir; grazoprevir may result in elevated lidocaine plasma concentrations. Lidocaine is a substrate of CYP3A; grazoprevir is a weak CYP3A inhibitor. If these drugs are used together, closely monitor for signs of adverse events.
Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Alafenamide: (Moderate) Monitor for lidocaine-related adverse reactions if coadministration with cobicistat is necessary. Lidocaine is a CYP3A4 substrate and cobicistat is a strong CYP3A4 inhibitor.
Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Disoproxil Fumarate: (Moderate) Monitor for lidocaine-related adverse reactions if coadministration with cobicistat is necessary. Lidocaine is a CYP3A4 substrate and cobicistat is a strong CYP3A4 inhibitor.
Enzalutamide: (Moderate) Monitor for decreased efficacy of lidocaine if coadministration of systemic lidocaine with enzalutamide is necessary; higher doses of lidocaine may be required. Lidocaine is a CYP3A4 substrate and enzalutamide is a strong CYP3A4 inducer.
Epinephrine: (Moderate) Monitor patients who receive epinephrine while concomitantly taking antiarrhythmics for the development of arrhythmias. Epinephrine may produce ventricular arrhythmias in patients who are on drugs that may sensitize the heart to arrhythmias.
Eslicarbazepine: (Moderate) Concomitant use of systemic lidocaine and eslicarbazepine may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; eslicarbazepine induces CYP3A4.
Esmolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Ethotoin: (Moderate) Lidocaine is a substrate for the cytochrome P450 isoenzymes 1A2 and 3A4. Ethotoin may enhance lidocaine clearance by inducing cytochrome P-450 enzymes.
Ethyl Chloride: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Etomidate: (Major) Local anesthetics may result in QT prolongation and should be used with caution with other agents that can prolong the QT interval including halogenated anesthetics (i.e., desflurane, enflurane, halothane, isoflurane, and sevoflurane). Also, If epinephrine is added to prilocaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
Etravirine: (Majo r) Etravirine is an inducer of CYP3A4; systemic lidocaine concentrations may be decreased with coadministration. Coadminister these drugs with caution. It is recommended to monitor lidocaine concentrations when possible.
Everolimus: (Moderate) Monitor for lidocaine toxicity if coadministration with everolimus is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A4 substrate and everolimus is a weak CYP3A4 inhibitor.
Famotidine: (Moderate) Concomitant use of systemic lidocaine and famotidine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; famotidine inhibits CYP1A2.
Felbamate: (Moderate) Concomitant use of systemic lidocaine and felbamate may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; felbamate induces CYP3A4.
Fentanyl: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for epidural analgesia or additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Flecainide: (Major) Although causality for torsades de pointes has not been established for flecainide, patients receiving concurrent drugs which have the potential for QT prolongation, such as local anesthetics, may have an increased risk of developing proarrhythmias. Use with caution.
Fluconazole: (Moderate) Concomitant use of systemic lidocaine and fluconazole may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; fluconazole inhibits CYP3A4.
Fluoxetine: (Moderate) Concomitant use of systemic lidocaine and fluoxetine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; fluoxetine inhibits CYP3A4.
Flutamide: (Moderate) Coadministration of lidocaine with oxidizing agents, such as flutamide, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as flutamide, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Fluvoxamine: (Moderate) Concomitant use of systemic lidocaine and fluvoxamine increases lidocaine exposure by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine plasma clearance is decreased by 41% to 60% and the mean half-life prolonged by 1 hour when used in combination with fluvoxamine. Lidocaine is a CYP1A2 and CYP3A4 substrate; fluvoxamine inhibits both of these hepatic isoenzymes.
Food: (Major) Advise patients to avoid cannabis use during lidocaine treatment due to decreased exposure of lidocaine which may alter its efficacy. Cannabis use induces CYP1A2 and lidocaine is a CYP1A2 substrate. The induction potential of cannabis is greatest with chronic inhalation. Other routes of administration or sporadic use may have less of an effect.
Fosamprenavir: (Moderate) Monitor for lidocaine toxicity if coadministration with fosamprenavir is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and fosamprenavir is a moderate CYP3A inhibitor.
Fosphenytoin: (Moderate) Coadministration of prilocaine with oxidizing agents, such as fosphenytoin, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Concomitant use of systemic lidocaine and fosphenytoin may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; fosphenytoin induces both hepatic isoenzymes. Additionally, coadministration of lidocaine with oxidizing agents, such as fosphenytoin, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Galantamine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary. (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used; dosage adjustments of the cholinesterase inhibitor may be necessary. In addition, inhibitors of CYP1A2, such as tacrine, could theoretically reduce lidocaine metabolism and increase the risk of toxicity when given concurrently. Also, rivastigmine is an acetylcholinesterase inhibitor and therefore is likely to exaggerate muscle relaxation under general anesthetics.
General anesthetics: (Major) Local anesthetics may result in QT prolongation and should be used with caution with other agents that can prolong the QT interval including halogenated anesthetics (i.e., desflurane, enflurane, halothane, isoflurane, and sevoflurane). Also, If epinephrine is added to prilocaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
Ginger, Zingiber officinale: (Minor) In vitro studies have demonstrated the positive inotropic effects of ginger, Zingiber officinale. It is theoretically possible that ginger could affect the action of antiarrhythmics, however, no clinical data are available.
Guaifenesin; Hydrocodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Homatropine; Hydrocodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Hyaluronidase, Recombinant; Immune Globulin: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
Hyaluronidase: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
Hydralazine; Isosorbide Dinitrate, ISDN: (Moderate) Coadministration of lidocaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Hydrocodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Hydrocodone; Ibuprofen: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Hydrocodone; Pseudoephedrine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Hydrocortisone; Pramoxine: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Hydromorphone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Hydroxyurea: (Moderate) Coadministration of lidocaine with oxidizing agents, such as hydroxyurea, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as hydroxyurea, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Ibuprofen; Famotidine: (Moderate) Concomitant use of systemic lidocaine and famotidine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; famotidine inhibits CYP1A2.
Ibuprofen; Oxycodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Idelalisib: (Major) Avoid concomitant use of idelalisib, a strong CYP3A inhibitor, with lidocaine, a CYP3A substrate, as lidocaine toxicities may be significantly increased. The AUC of a sensitive CYP3A substrate was increased 5.4-fold when coadministered with idelalisib.
Ifosfamide: (Moderate) Coadministration of lidocaine with oxidizing agents, such as ifosfamide, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as ifosfamide, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Imatinib: (Moderate) Monitor for lidocaine-related toxicity when administering with imatinib; lidocaine exposure may increase. Imatinib is a moderate CYP3A4 inhibitor; lidocaine is a CYP3A4 substrate.
Imipramine: (Major) If epinephrine is added to lidocaine for the purpose of infiltration and nerve block or spinal anesthesia, receipt of the product to a patient taking tricyclic antidepressants (TCA) may lead to severe, prolonged hypertension. In general, concurrent use of a local anesthetic solution containing epinephrine and a TCA should be avoided. If coadministration is necessary, careful patient monitoring is essential. (Major) Use prilocaine and tricyclic antidepressants together with caution. If epinephrine is added to prilocaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Administration of a phenothiazine or a butyrophenone may reduce or reverse the pressor effect of epinephrine.
Indinavir: (Moderate) Anti-retroviral protease inhibitors can inhibit hepatic cytochrome P450 3A4, an isoenzyme that is partially responsible for the metabolism of lidocaine. The concurrent use of systemic lidocaine and anti-retroviral protease inhibitors should be carefully monitored due to the potential for serious toxicity.
Isavuconazonium: (Moderate) Concomitant use of isavuconazonium with lidocaine may result in increased serum concentrations of lidocaine. Lidocaine is a substrate of the hepatic isoenzyme CYP3A4; isavuconazole, the active moiety of isavuconazonium, is a moderate inhibitor of this enzyme. Caution and close monitoring are advised if these drugs are used together.
Isocarboxazid: (Major) Patients receiving local anesthetics may have an increased risk of hypotension. Combined hypotensive effects are possible with use of MAOIs and spinal anesthetics. When local anesthetics containing sympathomimetic vasoconstrictors (e.g., epinephrine) are coadministered with MAOIs, severe and prolonged hypertension may occur. MAOIs can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Phenelzine and tranylcypromine are contraindicated for use for at least 10 days prior to elective surgery.
Isoflurane: (Major) Local anesthetics may result in QT prolongation and should be used with caution with other agents that can prolong the QT interval including halogenated anesthetics (i.e., desflurane, enflurane, halothane, isoflurane, and sevoflurane). Also, If epinephrine is added to prilocaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
Isoniazid, INH: (Moderate) Concomitant use of systemic lidocaine and isoniazid may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; isoniazid inhibits CYP3A4.
Isoniazid, INH; Pyrazinamide, PZA; Rifampin: (Moderate) Concomitant use of systemic lidocaine and isoniazid may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; isoniazid inhibits CYP3A4. (Moderate) Monitor for decreased efficacy of lidocaine if coadministration of systemic lidocaine with rifampin is necessary; higher doses of lidocaine may be required. Lidocaine is a substrate of CYP3A and CYP1A2, and rifampin is a strong CYP3A inducer and CYP1A2 inducer.
Isoniazid, INH; Rifampin: (Moderate) Concomitant use of systemic lidocaine and isoniazid may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; isoniazid inhibits CYP3A4. (Moderate) Monitor for decreased efficacy of lidocaine if coadministration of systemic lidocaine with rifampin is necessary; higher doses of lidocaine may be required. Lidocaine is a substrate of CYP3A and CYP1A2, and rifampin is a strong CYP3A inducer and CYP1A2 inducer.
Isosorbide Dinitrate, ISDN: (Moderate) Coadministration of lidocaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Isosorbide Mononitrate: (Moderate) Coadministration of lidocaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Itraconazole: (Moderate) Concomitant use of systemic lidocaine and itraconazole may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; itraconazole inhibits CYP3A4.
Ketamine: (Major) Local anesthetics may result in QT prolongation and should be used with caution with other agents that can prolong the QT interval including halogenated anesthetics (i.e., desflurane, enflurane, halothane, isoflurane, and sevoflurane). Also, If epinephrine is added to prilocaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
Ketoconazole: (Moderate) Concomitant use of systemic lidocaine and ketoconazole may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; ketoconazole inhibits CYP3A4.
Labetalol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Lacosamide: (Moderate) Use lacosamide with caution in patients taking concomitant medications that affect cardiac conduction, such as Class IB antiarrhythmics, because of the risk of AV block, bradycardia, or ventricular tachyarrhythmia. If use together is necessary, obtain an ECG prior to lacosamide initiation and after treatment has been titrated to steady-state. In addition, monitor patients receiving lacosamide via the intravenous route closely.
Lamotrigine: (Moderate) Consider ECG monitoring before and during concomitant use of lamotrigine with other sodium channel blockers known to impair atrioventricular and/or intraventricular cardiac conduction, such as class IB antiarrhythmics. Concomitant use of class IB antiarrhythmics with lamotrigine may increase the risk of proarrhythmia, especially in patients with clinically important structural or functional heart disease. In vitro testing showed that lamotrigine exhibits class IB antiarrhythmic activity at therapeutically relevant concentrations. (Moderate) Consider ECG monitoring before and during concomitant use of lamotrigine with other sodium channel blockers known to impair atrioventricular and/or intraventricular cardiac conduction, such as prilocaine. Concomitant use of prilocaine with lamotrigine may increase the risk of proarrhythmia, especially in patients with clinically important structural or functional heart disease. In vitro testing showed that lamotrigine exhibits class IB antiarrhythmic activity at therapeutically relevant concentrations.
Lansoprazole; Amoxicillin; Clarithromycin: (Moderate) Concomitant use of systemic lidocaine and clarithromycin may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; clarithromycin inhibits CYP3A4.
Lapatinib: (Major) Monitor for lidocaine toxicity if coadministration with lapatinib is necessary. Concomitant use of systemic lidocaine and lapatinib may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Lidocaine is a CYP3A4 substrate and lapatinib is a weak CYP3A4 inhibitor.
Lenacapavir: (Moderate) Monitor for lidocaine toxicity if coadministration with lenacapavir is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and lenacapavir is a moderate CYP3A inhibitor.
Leniolisib: (Moderate) Monitor for lidocaine toxicity if coadministration with leniolisib is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP1A2 substrate and leniolisib is a CYP1A2 inhibitor. Coadministration with another CYP1A2 inhibitor increased lidocaine exposure by 71%.
Lesinurad: (Moderate) Concomitant use of systemic lidocaine and lesinurad may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; lesinurad induces CYP3A4.
Lesinurad; Allopurinol: (Moderate) Concomitant use of systemic lidocaine and lesinurad may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; lesinurad induces CYP3A4.
Letermovir: (Moderate) An increase in the plasma concentration of lidocaine may occur if given with letermovir. In patients who are also receiving treatment with cyclosporine, the magnitude of this interaction may be amplified. Lidocaine is a CYP3A4 substrate. Letermovir is a moderate CYP3A4 inhibitor; however, when given with cyclosporine, the combined effect on CYP3A4 substrates may be similar to a strong CYP3A4 inhibitor.
Levamlodipine: (Moderate) Concomitant use of systemic lidocaine and amlodipine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; amlodipine inhibits CYP3A4.
Levobunolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Levoketoconazole: (Moderate) Concomitant use of systemic lidocaine and ketoconazole may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; ketoconazole inhibits CYP3A4.
Levorphanol: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Lidocaine; Epinephrine: (Moderate) Monitor patients who receive epinephrine while concomitantly taking antiarrhythmics for the development of arrhythmias. Epinephrine may produce ventricular arrhythmias in patients who are on drugs that may sensitize the heart to arrhythmias.
Lonafarnib: (Moderate) Monitor for lidocaine toxicity if coadministration with lonafarnib is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A4 substrate and lonafarnib is a strong CYP3A4 inhibitor.
Lopinavir; Ritonavir: (Moderate) Anti-retroviral protease inhibitors can inhibit hepatic cytochrome P450 3A4, an isoenzyme that is partially responsible for the metabolism of lidocaine. The concurrent use of systemic lidocaine and anti-retroviral protease inhibitors should be carefully monitored due to the potential for serious toxicity.
Mafenide: (Moderate) Coadministration of lidocaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Maribavir: (Moderate) Monitor for lidocaine toxicity if coadministration with maribavir is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and maribavir is a weak CYP3A inhibitor.
Menthol; Pramoxine: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Meperidine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Mepivacaine: (Moderate) Use mepivacaine and lidocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Use mepivacaine and prilocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Methadone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Methohexital: (Major) If epinephrine is added to prilocaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
Metoclopramide: (Moderate) Coadministration of lidocaine with metoclopramide may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other agents associated with methemoglobinemia. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with metoclopramide may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other agents associated with methemoglobinemia. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Metoprolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Metoprolol; Hydrochlorothiazide, HCTZ: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Mexiletine: (Major) Mexiletine is chemically and pharmacologically similar to lidocaine; cardiac and toxic effects may be additive. In addition, concurrent use may increase plasma lidocaine concentrations due to the displacement of lidocaine from tissue binding sites by mexiletine. If used together, monitor lidocaine plasma concentrations and adjust the dosage as required.
Minocycline: (Moderate) Injectable minocycline contains magnesium sulfate heptahydrate. Because of the CNS-depressant effects of magnesium sulfate, additive central-depressant effects can occur following concurrent administration with CNS depressants such as local anesthetics. Caution should be exercised when using these agents concurrently.
Mitotane: (Major) Use caution if mitotane and lidocaine are used concomitantly, and monitor for decreased efficacy of lidocaine and a possible change in dosage requirements. Mitotane is a strong CYP3A4 inducer and lidocaine is a CYP3A4 substrate; coadministration may result in decreased plasma concentrations of lidocaine.
Mivacurium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
Modafinil: (Moderate) Concomitant use of systemic lidocaine and modafinil may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; modafinil induces both isoenzymes.
Monoamine oxidase inhibitors: (Major) Patients receiving local anesthetics may have an increased risk of hypotension. Combined hypotensive effects are possible with use of MAOIs and spinal anesthetics. When local anesthetics containing sympathomimetic vasoconstrictors (e.g., epinephrine) are coadministered with MAOIs, severe and prolonged hypertension may occur. MAOIs can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Phenelzine and tranylcypromine are contraindicated for use for at least 10 days prior to elective surgery.
Morphine: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Morphine; Naltrexone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Nadolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Nebivolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Nebivolol; Valsartan: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Nefazodone: (Moderate) Concomitant use of systemic lidocaine and nefazodone may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; nefazodone inhibits CYP3A4.
Nelfinavir: (Moderate) Anti-retroviral protease inhibitors can inhibit hepatic cytochrome P450 3A4, an isoenzyme that is partially responsible for the metabolism of lidocaine. The concurrent use of systemic lidocaine and anti-retroviral protease inhibitors should be carefully monitored due to the potential for serious toxicity.
Neostigmine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary. (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used; dosage adjustments of the cholinesterase inhibitor may be necessary. In addition, inhibitors of CYP1A2, such as tacrine, could theoretically reduce lidocaine metabolism and increase the risk of toxicity when given concurrently. Also, rivastigmine is an acetylcholinesterase inhibitor and therefore is likely to exaggerate muscle relaxation under general anesthetics.
Neostigmine; Glycopyrrolate: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary. (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used; dosage adjustments of the cholinesterase inhibitor may be necessary. In addition, inhibitors of CYP1A2, such as tacrine, could theoretically reduce lidocaine metabolism and increase the risk of toxicity when given concurrently. Also, rivastigmine is an acetylcholinesterase inhibitor and therefore is likely to exaggerate muscle relaxation under general anesthetics.
Netupitant, Fosnetupitant; Palonosetron: (Moderate) Concomitant use of systemic lidocaine and netupitant may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; inhibition of CYP3A4 by netupitant can last for multiple days after a single dose.
Neuromuscular blockers: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
Nevirapine: (Minor) Monitor for reduced efficacy of lidocaine if coadministration with nevirapine is necessary. Concomitant use may decrease lidocaine exposure. Lidocaine is a CYP3A substrate and nevirapine is a weak CYP3A inducer.
Nilotinib: (Major) Avoid the concomitant use of nilotinib with other agents that prolong the QT interval. Systemic lidocaine has been established to have a causal association with QT prolongation and torsade de pointes. Additionally, nilotinib is a moderate CYP3A4 inhibitor and lidocaine is a CYP3A4 substrate; administering these drugs together may result in increased lidocaine levels. If the use of lidocaine is required, hold nilotinib therapy. If the use of nilotinib and lidocaine cannot be avoided, a lidocaine dose reduction may be necessary; close monitoring of the QT interval is recommended.
Nirmatrelvir; Ritonavir: (Moderate) Anti-retroviral protease inhibitors can inhibit hepatic cytochrome P450 3A4, an isoenzyme that is partially responsible for the metabolism of lidocaine. The concurrent use of systemic lidocaine and anti-retroviral protease inhibitors should be carefully monitored due to the potential for serious toxicity.
Nitrates: (Moderate) Coadministration of lidocaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Nitrofurantoin: (Moderate) Coadministration of lidocaine with oxidizing agents, such as nitrofurantoin, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as nitrofurantoin, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Nitroglycerin: (Moderate) Coadministration of lidocaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as nitrates, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Nortriptyline: (Major) If epinephrine is added to lidocaine for the purpose of infiltration and nerve block or spinal anesthesia, receipt of the product to a patient taking tricyclic antidepressants (TCA) may lead to severe, prolonged hypertension. In general, concurrent use of a local anesthetic solution containing epinephrine and a TCA should be avoided. If coadministration is necessary, careful patient monitoring is essential. (Major) Use prilocaine and tricyclic antidepressants together with caution. If epinephrine is added to prilocaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Administration of a phenothiazine or a butyrophenone may reduce or reverse the pressor effect of epinephrine.
Obeticholic Acid: (Moderate) Monitor for lidocaine toxicity if coadministration with obeticholic acid is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP1A2 substrate and obeticholic acid is a CYP1A2 inhibitor. Coadministration of another CYP1A2 inhibitor increased lidocaine exposure by 71%.
Olanzapine; Fluoxetine: (Moderate) Concomitant use of systemic lidocaine and fluoxetine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; fluoxetine inhibits CYP3A4.
Olmesartan; Amlodipine; Hydrochlorothiazide, HCTZ: (Moderate) Concomitant use of systemic lidocaine and amlodipine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; amlodipine inhibits CYP3A4.
Omeprazole; Amoxicillin; Rifabutin: (Moderate) Concomitant use of systemic lidocaine and rifabutin may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; rifabutin induces CYP3A4.
Oritavancin: (Moderate) Lidocaine is metabolized by CYP3A4; oritavancin is a weak CYP3A4 inducer. Plasma concentrations and efficacy of lidocaine may be reduced if these drugs are administered concurrently.
Osilodrostat: (Moderate) Monitor for lidocaine toxicity if coadministration with osilodrostat is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP1A2 and CYP3A4 substrate; osilodrostat is a moderate CYP1A2 inhibitor and weak CYP3A4 inhibitor.
Oxycodone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Oxymorphone: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic may allow for the use a lower i nitial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Pacritinib: (Moderate) Monitor for lidocaine toxicity if coadministration with pacritinib is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A4 and CYP1A2 substrate; pacritinib is a weak CYP3A4 and CYP1A2 inhibitor.
Palbociclib: (Moderate) Concomitant use of systemic lidocaine and palbociclib may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; palbociclib inhibits CYP3A4.
Pancuronium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
Pazopanib: (Moderate) Pazopanib is a weak inhibitor of CYP3A4. Coadministration of pazopanib and lidocaine, a CYP3A4 substrate, may cause an increase in systemic concentrations of lidocaine. Use caution when administering these drugs concomitantly.
Peginterferon Alfa-2b: (Major) Monitor for adverse effects associated with increased exposure to systemic lidocaine if peginterferon alfa-2b is coadministered. Peginterferon alfa-2b is a CYP1A2 inhibitor, while lidocaine is a CYP1A2 substrate.
Penicillin G Benzathine; Penicillin G Procaine: (Moderate) Coadministration of penicillin G procaine with other local anesthetics, such as lidocaine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue penicillin G procaine and any other local anesthetic. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of penicillin G procaine with other local anesthetics, such as prilocaine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue penicillin G procaine and any other local anesthetic. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Penicillin G Procaine: (Moderate) Coadministration of penicillin G procaine with other local anesthetics, such as lidocaine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue penicillin G procaine and any other local anesthetic. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of penicillin G procaine with other local anesthetics, such as prilocaine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue penicillin G procaine and any other local anesthetic. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Perindopril; Amlodipine: (Moderate) Concomitant use of systemic lidocaine and amlodipine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; amlodipine inhibits CYP3A4.
Perphenazine; Amitriptyline: (Major) If epinephrine is added to lidocaine for the purpose of infiltration and nerve block or spinal anesthesia, receipt of the product to a patient taking tricyclic antidepressants (TCA) may lead to severe, prolonged hypertension. In general, concurrent use of a local anesthetic solution containing epinephrine and a TCA should be avoided. If coadministration is necessary, careful patient monitoring is essential. (Major) Use prilocaine and tricyclic antidepressants together with caution. If epinephrine is added to prilocaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Administration of a phenothiazine or a butyrophenone may reduce or reverse the pressor effect of epinephrine.
Pertuzumab; Trastuzumab; Hyaluronidase: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
Phenelzine: (Major) Patients receiving local anesthetics may have an increased risk of hypotension. Combined hypotensive effects are possible with use of MAOIs and spinal anesthetics. When local anesthetics containing sympathomimetic vasoconstrictors (e.g., epinephrine) are coadministered with MAOIs, severe and prolonged hypertension may occur. MAOIs can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Phenelzine and tranylcypromine are contraindicated for use for at least 10 days prior to elective surgery.
Phenobarbital: (Moderate) Coadministration of prilocaine with oxidizing agents, such as phenobarbital, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Concomitant use of systemic lidocaine and phenobarbital may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; phenobarbital induces both hepatic isoenzymes. Additionally, coadministration of lidocaine with oxidizing agents, such as phenobarbital, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Phenobarbital; Hyoscyamine; Atropine; Scopolamine: (Moderate) Coadministration of prilocaine with oxidizing agents, such as phenobarbital, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Concomitant use of systemic lidocaine and phenobarbital may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; phenobarbital induces both hepatic isoenzymes. Additionally, coadministration of lidocaine with oxidizing agents, such as phenobarbital, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Phentermine; Topiramate: (Moderate) Concomitant use of systemic lidocaine and topiramate may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; topiramate induces CYP3A4.
Phenytoin: (Moderate) Coadministration of prilocaine with oxidizing agents, such as phenytoin, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Concomitant use of systemic lidocaine and phenytoin may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; phenytoin induces both hepatic isoenzymes. Additionally, coadministration of lidocaine with oxidizing agents, such as phenytoin, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Physostigmine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary. (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used; dosage adjustments of the cholinesterase inhibitor may be necessary. In addition, inhibitors of CYP1A2, such as tacrine, could theoretically reduce lidocaine metabolism and increase the risk of toxicity when given concurrently. Also, rivastigmine is an acetylcholinesterase inhibitor and therefore is likely to exaggerate muscle relaxation under general anesthetics.
Pindolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Pirtobrutinib: (Moderate) Monitor for lidocaine toxicity if coadministration with pirtobrutinib is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and pirtobrutinib is a weak CYP3A inhibitor.
Posaconazole: (Major) Posaconazole and lidocaine should be coadministered with caution due to an increased potential for lidocaine-related adverse events. Posaconazole is a potent inhibitor of CYP3A4, an isoenzyme partially responsible for the metabolism of lidocaine. These drugs used in combination may result in elevated lidocaine plasma concentrations, causing an increased risk for lidocaine-related adverse events.
Pramoxine: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Pramoxine; Zinc Acetate: (Moderate) Caution is advised if combining local anesthetics. The toxic effects of local anesthetics are additive. A major cause of adverse reactions appears to be excessive plasma concentrations, which may be due to accidental intravascular administration, slow metabolic degradation, or overdosage. In addition to additive toxic effects, rare and sometimes fatal cases of methemoglobinemia have been reported with the use of topical or oromucosal benzocaine-containing products. Clinicians should closely monitor patients for the development of methemoglobinemia when a combination local anesthetic is used during a procedure. If a patient becomes cyanotic or if elevated methemoglobin concentrations are suspected, immediately institute treatment to counteract methemoglobinemia (such as administration of methylene blue) as oxygen delivery is ineffective throughout the body until the condition is reversed. Patients who are receiving other drugs that can cause methemoglobin formation, such as prilocaine, are at greater risk for developing methemoglobinemia.
Prilocaine: (Moderate) Use lidocaine and prilocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Prilocaine; Epinephrine: (Moderate) Monitor patients who receive epinephrine while concomitantly taking antiarrhythmics for the development of arrhythmias. Epinephrine may produce ventricular arrhythmias in patients who are on drugs that may sensitize the heart to arrhythmias. (Moderate) Use lidocaine and prilocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Primaquine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as primaquine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Primidone: (Moderate) Coadministration of prilocaine with oxidizing agents, such as primidone, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Concomitant use of systemic lidocaine and primidone may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; phenobarbital, the active metabolite of primidone, induces both hepatic isoenzymes. Additionally, coadministration of lidocaine with oxidizing agents, such as primidone, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Procainamide: (Major) Concurrent use of systemic lidocaine and other antiarrhythmic drugs such as procainamide may result in additive or antagonistic cardiac effects and additive toxicity. Patients receiving more than one antiarrhythmic drug must be carefully monitored; dosage reduction may be necessary.
Procarbazine: (Major) Patients taking procarbazine should not be given local anesthetics containing sympathomimetic vasoconstrictors; coadministration may invoke a severe hypertensive reaction. Procarbazine should be discontinued for at least 10 days prior to elective surgery.
Propafenone: (Major) There is limited experience with the use of propafenone with Class IB antiarrhythmics. No significant effects on the pharmacokinetics of propafenone or lidocaine have been seen following their concomitant use in patients. However, the concomitant use of propafenone and lidocaine has been reported to increase the risks of central nervous system side effects of lidocaine. When propafenone is coadministered, the dose of lidocaine should be titrated to the desired therapeutic effects.
Propofol: (Major) Local anesthetics may result in QT prolongation and should be used with caution with other agents that can prolong the QT interval including halogenated anesthetics (i.e., desflurane, enflurane, halothane, isoflurane, and sevoflurane). Also, If epinephrine is added to prilocaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible. (Moderate) Concomitant use of systemic lidocaine and propofol may increase lidocaine plasma concentrations by reducing lidocaine clearance. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 substrate and propofol is a CYP3A4 inhibitor.
Propranolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Propranolol; Hydrochlorothiazide, HCTZ: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Protriptyline: (Major) If epinephrine is added to lidocaine for the purpose of infiltration and nerve block or spinal anesthesia, receipt of the product to a patient taking tricyclic antidepressants (TCA) may lead to severe, prolonged hypertension. In general, concurrent use of a local anesthetic solution containing epinephrine and a TCA should be avoided. If coadministration is necessary, careful patient monitoring is essential. (Major) Use prilocaine and tricyclic antidepressants together with caution. If epinephrine is added to prilocaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Administration of a phenothiazine or a butyrophenone may reduce or reverse the pressor effect of epinephrine.
Pyridostigmine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary. (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used; dosage adjustments of the cholinesterase inhibitor may be necessary. In addition, inhibitors of CYP1A2, such as tacrine, could theoretically reduce lidocaine metabolism and increase the risk of toxicity when given concurrently. Also, rivastigmine is an acetylcholinesterase inhibitor and therefore is likely to exaggerate muscle relaxation under general anesthetics.
Quinidine: (Major) Avoid concurrent use of quinidine with other antiarrhythmics with Class I activities, such as lidocaine. Concurrent use may result in additive or antagonistic cardiac effects and additive toxicity.
Quinine: (Moderate) Coadministration of prilocaine with oxidizing agents, such as quinine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Concomitant use of systemic lidocaine and quinine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; quinine inhibits CYP3A4. Additionally, coadministration of lidocaine with oxidizing agents, such as quinine, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Ranolazine: (Major) Ranolazine is an inhibitor of the cytochrome P450 (CYP) isoenzyme 3A, and lidocaine is a substrate for this pathway. Thus, ranolazine may theoretically reduce lidocaine clearance. If concurrent therapy with ranolazine is necessary, administer lidocaine parenteral infusions with caution and monitor lidocaine serum concentrations.
Rasburicase: (Moderate) Coadministration of lidocaine with oxidizing agents, such as rasburicase, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as rasburicase, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Remifentanil: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Ribociclib: (Moderate) Monitor for lidocaine-related adverse reactions if coadministration with ribociclib is necessary. Lidocaine is a CYP3A4 substrate and ribociclib is a strong CYP3A4 inhibitor.
Ribociclib; Letrozole: (Moderate) Monitor for lidocaine-related adverse reactions if coadministration with ribociclib is necessary. Lidocaine is a CYP3A4 substrate and ribociclib is a strong CYP3A4 inhibitor.
Rifabutin: (Moderate) Concomitant use of systemic lidocaine and rifabutin may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; rifabutin induces CYP3A4.
Rifampin: (Moderate) Monitor for decreased efficacy of lidocaine if coadministration of systemic lidocaine with rifampin is necessary; higher doses of lidocaine may be required. Lidocaine is a substrate of CYP3A and CYP1A2, and rifampin is a strong CYP3A inducer and CYP1A2 inducer.
Rifapentine: (Moderate) Monitor for decreased efficacy of lidocaine if coadministration of systemic lidocaine with rifapentine is necessary; higher doses of lidocaine may be required. Lidocaine is a CYP3A4 substrate and rifapentine is a strong CYP3A4 inducer.
Ritlecitinib: (Moderate) Monitor for lidocaine toxicity if coadministration with ritlecitinib is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP1A2 and CYP3A substrate and ritlecitinib is a moderate CYP1A2 and CYP3A inhibitor. Coadministration of another CYP1A2 inhibitor increased lidocaine exposure by 71%.
Ritonavir: (Moderate) Anti-retroviral protease inhibitors can inhibit hepatic cytochrome P450 3A4, an isoenzyme that is partially responsible for the metabolism of lidocaine. The concurrent use of systemic lidocaine and anti-retroviral protease inhibitors should be carefully monitored due to the potential for serious toxicity.
Rituximab; Hyaluronidase: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
Rivastigmine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary. (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used; dosage adjustments of the cholinesterase inhibitor may be necessary. In addition, inhibitors of CYP1A2, such as tacrine, could theoretically reduce lidocaine metabolism and increase the risk of toxicity when given concurrently. Also, rivastigmine is an acetylcholinesterase inhibitor and therefore is likely to exaggerate muscle relaxation under general anesthetics.
Rocuronium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
Ropivacaine: (Moderate) Use lidocaine and ropivacaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Use ropivacaine and prilocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Rucaparib: (Moderate) Monitor for an increase in lidocaine-related adverse reactions if coadministration with rucaparib is necessary. Lidocaine is a CYP1A2 substrate and rucaparib is a moderate CYP1A2 inhibitor. Coadministration may increase lidocaine plasma concentrations.
Saquinavir: (Contraindicated) The concurrent use of systemic lidocaine and saquinavir boosted with ritonavir is contraindicated due to the risk of life threatening arrhythmias such as torsades de pointes (TdP). Saquinavir boosted with ritonavir is a potent inhibitor of CYP3A4, an isoenzyme partially responsible for the metabolism of lidocaine. These drugs used together may result in large increases in lidocaine serum concentrations, which could cause fatal cardiac arrhythmias. Additionally, saquinavir boosted with ritonavir causes dose-dependent QT and PR prolongation; avoid use with other drugs that may prolong the QT or PR interval, such as lidocaine.
Selpercatinib: (Moderate) Monitor for lidocaine toxicity if coadministration with selpercatinib is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A4 substrate and selpercatinib is a weak CYP3A4 inhibitor.
Sevoflurane: (Major) Local anesthetics may result in QT prolongation and should be used with caution with other agents that can prolong the QT interval including halogenated anesthetics (i.e., desflurane, enflurane, halothane, isoflurane, and sevoflurane). Also, If epinephrine is added to prilocaine, do not use the mixture in a patient during or following treatment with general anesthetics. Concurrent use has been associated with the development of cardiac arrhythmias, and should be avoided, if possible.
Sodium Phenylbutyrate; Taurursodiol: (Moderate) Monitor for decreased efficacy of lidocaine if coadministration of systemic lidocaine with taurursodiol is necessary; higher doses of lidocaine may be required. Lidocaine is a CYP1A2 substrate and taurursodiol is a CYP1A2 inducer.
Spironolactone: (Moderate) Monitor for lidocaine toxicity if coadministration with spironolactone is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A4 substrate and spironolactone is a weak CYP3A4 inhibitor.
Spironolactone; Hydrochlorothiazide, HCTZ: (Moderate) Monitor for lidocaine toxicity if coadministration with spironolactone is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A4 substrate and spironolactone is a weak CYP3A4 inhibitor.
St. John's Wort, Hypericum perforatum: (Moderate) Concomitant use of systemic lidocaine and St. John's Wort may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; St. John's Wort induces CYP3A4.
Streptogramins: (Moderate) Coadministration of lidocaine with dalfopristin; quinupristin may result in elevated lidocaine plasma concentrations. If these drugs are used together, closely monitor for signs of lidocaine-related adverse events. Lidocaine is a substrate of CYP3A; dalfopristin; quinupristin is a weak CYP3A inhibitor.
Succinylcholine: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
Sufentanil: (Moderate) The use of these drugs together must be approached with caution. Although commonly used together for additive analgesic effects, the patient must be monitored for respiratory depression, hypotension, and excessive sedation due to additive effects on the CNS and blood pressure. In rare instances, serious morbidity and mortality has occurred. Limit the use of opiate pain medications with local anesthetics to only patients for whom alternative treatment options are inadequate. If concurrent use is necessary, use the lowest effective doses and minimum treatment durations needed to achieve the desired clinical effect. The use of the local anesthetic will allow for the use a lower initial dose of the opiate and then the doses can be titrated to proper clinical response. Educate patients about the risks and symptoms of respiratory depression and sedation.
Sulfadiazine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Sulfamethoxazole; Trimethoprim, SMX-TMP, Cotrimoxazole: (Moderate) Coadministration of lidocaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Sulfasalazine: (Moderate) Coadministration of lidocaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Sulfonamides: (Moderate) Coadministration of lidocaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as sulfonamides, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Tacrine: (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used. Also, local anesthetics interfere with the release of acetylcholine. Dosage adjustment of the cholinesterase inhibitor may be necessary. (Moderate) Local anesthetics can antagonize the effects of cholinesterase inhibitors by inhibiting neuronal transmission in skeletal muscle, especially if large doses of local anesthetics are used; dosage adjustments of the cholinesterase inhibitor may be necessary. In addition, inhibitors of CYP1A2, such as tacrine, could theoretically reduce lidocaine metabolism and increase the risk of toxicity when given concurrently. Also, rivastigmine is an acetylcholinesterase inhibitor and therefore is likely to exaggerate muscle relaxation under general anesthetics.
Telmisartan; Amlodipine: (Moderate) Concomitant use of systemic lidocaine and amlodipine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; amlodipine inhibits CYP3A4.
Teriflunomide: (Moderate) As teriflunomide is a weak inducer of CYP1A2, exposure to lidocaine, a CYP1A2 substrate, may be reduced. Caution should be exercised with concurrent use. Patients should be monitored for loss of antiarrhythmic effect if teriflunomide therapy is initiated. Conversely, lidocaine doses may need adjustment if teriflunomide treatment is discontinued.
Tetracaine: (Moderate) Use tetracaine and lidocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Use tetracaine and prilocaine together with caution. Monitor cardiovascular and respiratory vital signs, as well as the patient's state of consciousness if used concurrently due to potential for additive CNS and/or cardiovascular toxic effects. Manifestations of toxicity may include CNS excitation and/or depression, cardiac conduction depression, or peripheral vasodilation. Additionally, coadministration may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue local anesthetic use. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Ticagrelor: (Moderate) Concomitant use of systemic lidocaine and ticagrelor may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; ticagrelor inhibits CYP3A4.
Ticlopidine: (Moderate) Concomitant use of systemic lidocaine and ticlopidine may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; ticlopidine inhibits CYP1A2.
Timolol: (Major) Drugs such as beta-blockers that decrease cardiac output reduce hepatic blood flow and thereby decrease lidocaine hepatic clearance. Also, opposing effects on conduction exist between lidocaine and beta-blockers while their effects to decrease automaticity may be additive. Propranolol has been shown to decrease lidocaine clearance and symptoms of lidocaine toxicity have been seen as a result of this interaction. This interaction is possible with other beta-blocking agents since most decrease hepatic blood flow. Monitoring of lidocaine concentrations is recommended during concomitant therapy with beta-blockers. (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
Tipranavir: (Moderate) Anti-retroviral protease inhibitors can inhibit hepatic cytochrome P450 3A4, an isoenzyme that is partially responsible for the metabolism of lidocaine. The concurrent use of systemic lidocaine and anti-retroviral protease inhibitors should be carefully monitored due to the potential for serious toxicity.
Topiramate: (Moderate) Concomitant use of systemic lidocaine and topiramate may decrease lidocaine plasma concentrations. Higher lidocaine doses may be required; titrate to effect. Lidocaine is a CYP3A4 and CYP1A2 substrate; topiramate induces CYP3A4.
Tramadol; Acetaminophen: (Moderate) Coadministration of lidocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as acetaminophen, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Trandolapril; Verapamil: (Moderate) Concomitant use of systemic lidocaine and verapamil may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; verapamil inhibits both hepatic isoenzymes.
Tranylcypromine: (Major) Patients receiving local anesthetics may have an increased risk of hypotension. Combined hypotensive effects are possible with use of MAOIs and spinal anesthetics. When local anesthetics containing sympathomimetic vasoconstrictors (e.g., epinephrine) are coadministered with MAOIs, severe and prolonged hypertension may occur. MAOIs can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Phenelzine and tranylcypromine are contraindicated for use for at least 10 days prior to elective surgery.
Trastuzumab; Hyaluronidase: (Moderate) Hyaluronidase, when used in combination with local anesthetics, hastens the onset of analgesia and reduces the swelling caused by local infiltration; this interaction is beneficial and is the reason hyaluronidase is used adjunctively in local infiltrative anesthesia techniques. However, the wider spread of the local anesthetic solution may increase the systemic absorption of the local anesthetic, which shortens the duration of anesthetic action and tends to increase the potential risk for systemic side effects.
Tretinoin; Benzoyl Peroxide: (Moderate) Concurrent use of benzoyl peroxide and topical anesthetics may decrease the efficacy of the anesthetic. In a clinical study, an estimated 75% increase in patient-reported, prick-induced pain was noted in areas treated with both 5% benzoyl peroxide and 6% benzocaine cream as compared to areas treated with 6% benzocaine cream alone. Investigators attributed the decreased anesthetic effect to a breakdown of the benzocaine molecule by either or both benzoyl peroxide or benzoyl peroxide-derived free radicals. It is recommended that the skin area that is to be topically anesthetized have no previous treatment with benzoyl peroxide or that the skin is thoroughly washed prior to the application of the anesthetic.
Tricyclic antidepressants: (Major) If epinephrine is added to lidocaine for the purpose of infiltration and nerve block or spinal anesthesia, receipt of the product to a patient taking tricyclic antidepressants (TCA) may lead to severe, prolonged hypertension. In general, concurrent use of a local anesthetic solution containing epinephrine and a TCA should be avoided. If coadministration is necessary, careful patient monitoring is essential. (Major) Use prilocaine and tricyclic antidepressants together with caution. If epinephrine is added to prilocaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Administration of a phenothiazine or a butyrophenone may reduce or reverse the pressor effect of epinephrine.
Trimipramine: (Major) If epinephrine is added to lidocaine for the purpose of infiltration and nerve block or spinal anesthesia, receipt of the product to a patient taking tricyclic antidepressants (TCA) may lead to severe, prolonged hypertension. In general, concurrent use of a local anesthetic solution containing epinephrine and a TCA should be avoided. If coadministration is necessary, careful patient monitoring is essential. (Major) Use prilocaine and tricyclic antidepressants together with caution. If epinephrine is added to prilocaine, severe and prolonged hypertension may occur in a patient taking a TCA. Tricyclic antidepressants can increase the sensitivity to epinephrine by inhibiting epinephrine reuptake or metabolism. If concurrent therapy is necessary, carefully monitor the patient. Administration of a phenothiazine or a butyrophenone may reduce or reverse the pressor effect of epinephrine.
Trofinetide: (Moderate) Monitor for lidocaine toxicity if coadministration with trofinetide is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and trofinetide is a weak CYP3A inhibitor.
Tucatinib: (Moderate) Monitor for lidocaine toxicity if coadministration with tucatinib is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A4 substrate and tucatinib is a strong CYP3A4 inhibitor.
Valproic Acid, Divalproex Sodium: (Moderate) Coadministration of lidocaine with oxidizing agents, such as valproic acid, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue lidocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen. (Moderate) Coadministration of prilocaine with oxidizing agents, such as valproic acid, may increase the risk of developing methemoglobinemia. Monitor patients closely for signs and symptoms of methemoglobinemia if coadministration is necessary. If methemoglobinemia occurs or is suspected, discontinue prilocaine and any other oxidizing agents. Depending on the severity of symptoms, patients may respond to supportive care; more severe symptoms may require treatment with methylene blue, exchange transfusion, or hyperbaric oxygen.
Vecuronium: (Moderate) Concomitant use of neuromuscular blockers and local anesthetics may prolong neuromuscular blockade. The use of a peripheral nerve stimulator is strongly recommended to evaluate the level of neuromuscular blockade, to assess the need for additional doses of neuromuscular blocker, and to determine whether adjustments need to be made to the dose with subsequent administration.
Verapamil: (Moderate) Concomitant use of systemic lidocaine and verapamil may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; verapamil inhibits both hepatic isoenzymes.
Viloxazine: (Moderate) Monitor for lidocaine toxicity if coadministration with viloxazine is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP1A2 and CYP3A substrate and viloxazine is a strong CYP1A2 and weak CYP3A inhibitor. Coadministration of another CYP1A2 inhibitor increased lidocaine exposure by 71%.
Vonoprazan; Amoxicillin: (Moderate) Monitor for lidocaine toxicity if coadministration with vonoprazan is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and vonoprazan is a weak CYP3A inhibitor.
Vonoprazan; Amoxicillin; Clarithromycin: (Moderate) Concomitant use of systemic lidocaine and clarithromycin may increase lidocaine plasma concentrations by decreasing lidocaine clearance and therefore prolonging the elimination half-life. Monitor for lidocaine toxicity if used together. Lidocaine is a CYP3A4 and CYP1A2 substrate; clarithromycin inhibits CYP3A4. (Moderate) Monitor for lidocaine toxicity if coadministration with vonoprazan is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and vonoprazan is a weak CYP3A inhibitor.
Voriconazole: (Moderate) Monitor for lidocaine-related adverse reactions if coadministration with voriconazole is necessary. Lidocaine is a CYP3A4 substrate and voriconazole is a strong CYP3A4 inhibitor.
Voxelotor: (Moderate) Monitor for lidocaine toxicity if coadministration with voxelotor is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP3A substrate and voxelotor is a moderate CYP3A inhibitor.
Zafirlukast: (Minor) Zafirlukast inhibits the CYP3A4 isoenzymes and should be used cautiously in patients stabilized on drugs metabolized by CYP3A4, such as lidocaine.
Zileuton: (Moderate) Monitor for lidocaine toxicity if coadministration with zileuton is necessary as concurrent use may increase lidocaine exposure. Lidocaine is a CYP1A2 substrate and zileuton is a CYP1A2 inhibitor. Coadministration of another CYP1A2 inhibitor increased lidocaine exposure by 71%.

zileuton is a CYP1A2 inhibitor. Coadministration of another CYP1A2 inhibitor increased lidocaine exposure by 71%.

How Supplied

ANODYNE LPT/DermacinRx/DermacinRx Empricaine/DermacinRx Prizopak/Dolotranz/EMLA/IV Novice Pack/Leva Set/Lidocaine, Prilocaine/Lido-Prilo Caine/Lidotor/LiProZonePak/LIVIXIL Pak/LP Lite Pak/Medolor Pak with Tegaderm Dressing/Microvix LP/Nuvakaan/Nuvakaan-II/Port-Prep/PrepIV/PRILOHEAL PLUS 30/Prilovix/Prilovix Lite/Prilovix Lite Plus/Prilovix Plus/Prilovix Ultralite/Prilovix Ultralite Plus/Prilovixil/Prizopak-II/REAL HEAL-I/Relador/Soluline/SOLUPICC/VallaDerm-90 Topical Cream: 2.5-2.5%, 2.5-4-2.5%
Dolotranz Topical Gel: 2.5-4-2.5%
Lidocaine, Prilocaine/Oraqix Periodontal Gel: 2.5-2.5%

Maximum Dosage

For pediatric use, the maximum total dose of EMLA should be restricted to that which corresponds to the child's weight.

Adults

The maximum recommended duration of exposure of the EMLA cream or disk is 4 hours; 8.5 grams (5 cartridges) of the Oraqix periodontal gel per treatment session.

Elderly

The maximum recommended duration of exposure of the EMLA cream or disk is 4 hours; 8.5 grams (5 cartridges) of the Oraqix periodontal gel per treatment session.

Adolescents

The maximum recommended duration of exposure of the EMLA cream or disk is 4 hours; safety and efficacy of the Oraqix periodontal gel has not been established.

Children

7—12 years and > 20 kg: 20 g total dose of the EMLA cream or disk; maximal application area should not exceed 200 cm2 and maximum application time is 4 hours; safety and efficacy of the Oraqix periodontal gel has not been established.
1—6 years and > 10 kg: 10 g total dose of the EMLA cream or disk; maximal application area should not exceed 100 cm2 and maximum application time is 4 hours; safety and efficacy of the Oraqix periodontal gel has not been established.

Infants

3—12 months and > 5 kg: 2 g total dose of the EMLA cream or disk; maximal application area should not exceed 20 cm2 and maximum application time is 4 hours; safety and efficacy of the Oraqix periodontal gel has not been established.
up to 3 months or < 5 kg: 1 g total dose of the EMLA cream or disk; maximal application area should not exceed 10 cm2 and maximum application time is 1 hour; safety and efficacy of the Oraqix periodontal gel has not been established.

Neonates

Neonates > 37 weeks gestational age: 1 g total dose of the EMLA cream or disk; maximal application area should not exceed 10 cm2 and maximum application time is 1 hour; safety and efficacy of the Oraqix periodontal gel has not been established.
Neonates <= 37 weeks gestational age: Use not recommended.

Mechanism Of Action

Lidocaine and prilocaine are amide-type local anesthetics that produce a local anesthetic action by stabilization of neuronal membranes. Specifically, lidocaine and prilocaine inhibit the ionic fluxes required for the initiation and conduction of impulses. Dermal analgesia is achieved because the cream release lidocaine and prilocaine into the epidermal and dermal layers of the skin, and the drugs accumulate in the vicinity of dermal pain receptors and nerve endings.[41938] [53462]

Pharmacokinetics

Lidocaine; prilocaine is applied topically. Lidocaine and prilocaine bind mainly to 1-acid glycoprotein. The extent of plasma protein binding is 70% for lidocaine and 55% for prilocaine. Lidocaine is extensively metabolized in the liver into 2 active compounds, monoethylglycinexylidide (MEGX) and glycinexylidide (GX), which possess 100% and 25% of the potency of lidocaine, respectively. The major metabolic pathway, sequential N-demethylation to MEGX and GX, is primarily mediated by CYP1A2 with a minor role of CYP3A4. Prilocaine is metabolized in both the liver and the kidneys by amidases. The metabolite, o-toluidine, is hydrolyzed to 4- and 6-hydroxytoluidine, which are renally eliminated. The mean terminal half-life of lidocaine, prilocaine, and o-toluidine after application of the periodontal gel is 3.6 hours, 2.8 hours, and 4 hours, respectively. It is unknown if lidocaine or prilocaine are metabolized within the skin or mucous membranes.
 
Affected cytochrome P450 isoenzymes and drug transporters: CYP1A2, CYP3A4
Lidocaine is extensively metabolized in the liver into 2 active compounds, monoethylglycinexylidide (MEGX) and glycinexylidide (GX). The major metabolic pathway, sequential N-demethylation to MEGX and GX, is primarily mediated by CYP1A2 with a minor role of CYP3A4.

Topical Route

Cream: The amount of lidocaine and prilocaine absorbed into the systemic circulation from the cream is directly related to the duration of application and to the area over which it is applied. When 60 g of cream is applied over 400 cm2 for 24 hours, peak lidocaine and prilocaine blood concentrations are 280 ng/mL and 140 ng/mL, respectively, or about 1/20 and 1/36, respectively, of the systemic toxic concentrations. Application of the cream to broken or inflamed skin or to more than 2,000 cm2 of skin results in higher plasma concentrations, which could result in systemic adverse effects in susceptible individuals. Application of 10 g of the cream for 10 to 60 minutes to vaginal fornices results in lidocaine plasma concentrations of 148 to 641 ng/mL and prilocaine plasma concentrations of 40 to 346 ng/mL.[53462]
 
Periodontal Gel: The mean serum maximum concentration of lidocaine and prilocaine is 182 ng/mL and 77 ng/mL, respectively after periodontal gel application of 0.9 to 3.5 grams via the oral mucous membranes. A total of 8 to 8.5 grams applied over 3 hours yields a mean serum maximum concentration of 284 ng/mL (range, 157 to 552 ng/mL) for lidocaine and 106 ng/ml (range, 53 to 181 ng/mL) for prilocaine. The median time to the maximum serum concentration after the single application is 30 minutes (range, 20 to 40 minutes) and after the cumulative dose is 200 minutes (range, 120 to 200 minutes).[41938]

Pregnancy And Lactation
Pregnancy

Caution should be used when lidocaine; prilocaine is used during breast-feeding. Lidocaine and probably prilocaine are excreted in breast milk. The milk to plasma ratio of lidocaine is 0.4 and is not determined for prilocaine. Among 27 women who received lidocaine as an epidural anesthetic for cesarean section, a milk:plasma ratio of 1.07 +/- 0.82 was found by using AUC values; a similar milk:plasma ratio was found 5 to 6 hours after a single lidocaine 20 mg injection for a dental procedure. Thus, the estimated maximum total daily dose of lidocaine delivered to the infant via breast milk would be approximately 36 mcg/kg. There are no data for prilocaine, but lidocaine is considered generally compatible with breast-feeding by previous American Academy of Pediatrics (AAP) recommendations. Based on these data and the low concentrations of lidocaine and prilocaine found in the plasma after topical administration, the use of lidocaine; prilocaine cream in recommended doses is unlikely to cause adverse effects in nursing infants. If a topical preparation of lidocaine; prilocaine is used during breast-feeding, the infant's skin should not come into direct contact with areas of the mother's skin that have been treated. Very young children are more susceptible to methemoglobinemia. Monitor such patients closely for signs and symptoms of methemoglobinemia. When lidocaine and other local anesthetics are used for dental or other short term, limited local anesthesia, the healthy term infant can generally safely nurse as soon as the mother is awake and alert. For dental anesthesia, dental products containing lidocaine alone may be a preferred alternative; no contraindications to the use of such local anesthetics exist when used during lactation. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally ingested drug, healthcare providers are encouraged to report the adverse effect to the FDA.