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NORVIR- ritonavir tablet, film coated NORVIR- ritonavir solution NORVIR- ritonavir powder AbbVie Inc.
Co-administration of NORVIR with several classes of drugs including sedative hypnotics, antiarrhythmics, or ergot alkaloid preparations may result in potentially serious and/or life-threatening adverse events due to possible effects of NORVIR on the hepatic metabolism of certain drugs. Review medications taken by patients prior to prescribing NORVIR or when prescribing other medications to patients already taking NORVIR. (4, 5.1)
NORVIR tablets and oral solution are HIV protease inhibitors indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection (1)
NORVIR oral powder is indicated in combination with other antiretroviral agents for the treatment of pediatric patients with HIV-1 infection (1)
The following have been observed in patients receiving NORVIR:
The most frequently reported adverse drug reactions among patients receiving NORVIR alone or in combination with other antiretroviral drugs were gastrointestinal (including diarrhea, nausea, vomiting, abdominal pain (upper and lower), neurological disturbances (including paresthesia and oral paresthesia), rash, and fatigue/asthenia (6.1)
To report SUSPECTED ADVERSE REACTIONS, contact AbbVie Inc. at 1-800-633-9110 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
See 17 for PATIENT COUNSELING INFORMATION and FDA-approved patient labeling.
Co-administration of NORVIR with several classes of drugs including sedative hypnotics, antiarrhythmics, or ergot alkaloid preparations may result in potentially serious and/or life-threatening adverse events due to possible effects of NORVIR on the hepatic metabolism of certain drugs. Review medications taken by patients prior to prescribing NORVIR or when prescribing other medications to patients already taking NORVIR [see Contraindications (4), Warnings and Precautions (5.1)].
NORVIR tablets and oral solution are indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection.
NORVIR oral powder is indicated in combination with other antiretroviral agents for the treatment of pediatric patients with HIV-1 infection.
General Dosing Guidelines
Patients who take the 600 mg twice daily soft gel capsule NORVIR dose may experience more gastrointestinal side effects such as nausea, vomiting, abdominal pain or diarrhea when switching from the soft gel capsule to the tablet formulation because of greater maximum plasma concentration (Cmax) achieved with the tablet formulation relative to the soft gel capsule [see Clinical Pharmacology (12.3)]. Patients should also be aware that these adverse events (gastrointestinal or paresthesias) may diminish as therapy is continued.
Because NORVIR oral solution contains ethanol and propylene glycol, it is not recommended for use with polyurethane feeding tubes due to potential incompatibility. Feeding tubes that are compatible with ethanol and propylene glycol, such as silicone and polyvinyl chloride (PVC) feeding tubes, can be used for administration of NORVIR oral solution. Follow instructions for use of the feeding tube to administer the medicine.
Recommended Dosage for Treatment of HIV-1:
The recommended dosage of NORVIR is 600 mg twice daily by mouth to be taken with meals. Use of a dose titration schedule may help to reduce treatment-emergent adverse events while maintaining appropriate ritonavir plasma levels. NORVIR should be started at no less than 300 mg twice daily and increased at 2 to 3 day intervals by 100 mg twice daily. The maximum dose of 600 mg twice daily should not be exceeded upon completion of the titration [see Dosage and Administration (2.6)].
NORVIR oral solution is not recommended during pregnancy due to its ethanol content. NORVIR oral solution contains the excipients ethanol (approx. 43% v/v) and propylene glycol (approx. 27% w/v) [see Use in Specific Populations (8.1)].
NORVIR must be used in combination with other antiretroviral agents [see Dosage and Administration (2)]. The recommended dosage of NORVIR in pediatric patients older than 1 month is 350 to 400 mg per m2 twice daily by mouth to be taken with meals and should not exceed 600 mg twice daily. NORVIR should be started at 250 mg per m2 twice daily and increased at 2 to 3 day intervals by 50 mg per m2 twice daily. If patients do not tolerate 400 mg per m2 twice daily due to adverse events, the highest tolerated dose may be used for maintenance therapy in combination with other antiretroviral agents, however, alternative therapy should be considered [see Dosage and Administration (2.6)].
Pediatric Dosage Guidelines for Oral Solution
NORVIR oral solution should not be administered to neonates before a postmenstrual age (first day of the mother’s last menstrual period to birth plus the time elapsed after birth) of 44 weeks has been attained [see Warnings and Precautions (5.2)].
NORVIR oral solution contains the excipients ethanol (approx. 43% v/v) and propylene glycol (approx. 27% w/v). Special attention should be given to accurate calculation of the dose of NORVIR, transcription of the medication order, dispensing information and dosing instructions to minimize the risk for medication errors, and overdose. This is especially important for young children. Total amounts of ethanol and propylene glycol from all medicines that are to be given to pediatric patients 1 to 6 months of age should be taken into account in order to avoid toxicity from these excipients [see Warnings and Precautions (5.2) and Overdosage (10)]. When possible, dose should be administered using a calibrated dosing syringe.
Body surface area (BSA) can be calculated as follows1:
Pediatric Dosage Guidelines for Oral Powder
NORVIR oral powder should be used only for dosing increments of 100 mg. NORVIR powder should not be used for doses less than 100 mg or for incremental doses between 100 mg intervals. NORVIR oral solution is the preferred formulation for patients requiring doses less than 100 mg or incremental doses between 100 mg intervals.
For details on the preparation and administration of NORVIR oral powder (see Instructions for Use). NORVIR oral powder should only be used for dosing increments of 100 mg.
Prepare the dose using the required number of packets. For example, use one packet for doses of 100 mg and two packets for doses of 200 mg. Pour and mix the entire contents of each packet over soft food or liquid. All of the powder mixed with soft food or liquid should be administered within 2 hours of preparation. If not administered within 2 hours of preparation, the mixture should be discarded and a new dose prepared.
The prescribed dose of NORVIR oral powder can be administered via a feeding tube after being mixed with water (see Instructions for Use). Follow the instructions for the feeding tube to administer the medicine.
Dose reduction of NORVIR is necessary when used with other protease inhibitors: atazanavir, darunavir, fosamprenavir, saquinavir, and tipranavir.
Prescribers should consult the full prescribing information and clinical study information of these protease inhibitors if they are co-administered with a reduced dose of ritonavir [see Warnings and Precautions (5.1), and Drug Interactions (7)].
White film-coated ovaloid tablets debossed with the "a" logo and the code NK providing 100 mg ritonavir.
Orange-colored liquid containing 600 mg ritonavir per 7.5 mL marked dosage cup (80 mg per mL).
Beige/pale yellow to yellow powder in child-resistant packet. Each packet contains 100 mg of ritonavir.
Initiation of NORVIR, a CYP3A inhibitor, in patients receiving medications metabolized by CYP3A or initiation of medications metabolized by CYP3A in patients already receiving NORVIR, may increase plasma concentrations of medications metabolized by CYP3A. Initiation of medications that inhibit or induce CYP3A may increase or decrease concentrations of NORVIR, respectively. These interactions may lead to:
When co-administering NORVIR with other protease inhibitors, see the full prescribing information for that protease inhibitor including important Warnings and Precautions.
See Table 4 for steps to prevent or manage these possible and known significant drug interactions, including dosing recommendations [see Drug Interactions (7)]. Consider the potential for drug interactions prior to and during NORVIR therapy; review concomitant medications during NORVIR therapy, and monitor for the adverse reactions associated with the concomitant medications [see Contraindications (4) and Drug Interactions (7)].
NORVIR oral solution contains the excipients ethanol (approx. 43% v/v) and propylene glycol (approx. 27% w/v). When administered concomitantly with propylene glycol, ethanol competitively inhibits the metabolism of propylene glycol, which may lead to elevated concentrations. Preterm neonates may be at an increased risk of propylene glycol-associated adverse events due to diminished ability to metabolize propylene glycol, thereby leading to accumulation and potential adverse events. Postmarketing life-threatening cases of cardiac toxicity (including complete AV block, bradycardia, and cardiomyopathy), lactic acidosis, acute renal failure, CNS depression and respiratory complications leading to death have been reported, predominantly in preterm neonates receiving lopinavir/ritonavir oral solution which also contains the excipients ethanol and propylene glycol.
NORVIR oral solution should not be used in preterm neonates in the immediate postnatal period because of possible toxicities. However, if the benefit of using NORVIR oral solution to treat HIV infection in infants immediately after birth outweighs the potential risks, infants should be monitored closely for increases in serum osmolality and serum creatinine, and for toxicity related to NORVIR oral solution including: hyperosmolality, with or without lactic acidosis, renal toxicity, CNS depression (including stupor, coma, and apnea), seizures, hypotonia, cardiac arrhythmias and ECG changes, and hemolysis. Total amounts of ethanol and propylene glycol from all medicines that are to be given to infants should be taken into account in order to avoid toxicity from these excipients [see Dosage and Administration (2.4) and Overdosage (10)].
Hepatic transaminase elevations exceeding 5 times the upper limit of normal, clinical hepatitis, and jaundice have occurred in patients receiving NORVIR alone or in combination with other antiretroviral drugs (see Table 3). There may be an increased risk for transaminase elevations in patients with underlying hepatitis B or C. Therefore, caution should be exercised when administering NORVIR to patients with pre-existing liver diseases, liver enzyme abnormalities, or hepatitis. Increased AST/ALT monitoring should be considered in these patients, especially during the first three months of NORVIR treatment [see Use in Specific Populations (8.6)].
There have been postmarketing reports of hepatic dysfunction, including some fatalities. These have generally occurred in patients taking multiple concomitant medications and/or with advanced AIDS.
Pancreatitis has been observed in patients receiving NORVIR therapy, including those who developed hypertriglyceridemia. In some cases fatalities have been observed. Patients with advanced HIV disease may be at increased risk of elevated triglycerides and pancreatitis [see Warnings and Precautions (5.7)]. Pancreatitis should be considered if clinical symptoms (nausea, vomiting, abdominal pain) or abnormalities in laboratory values (such as increased serum lipase or amylase values) suggestive of pancreatitis should occur. Patients who exhibit these signs or symptoms should be evaluated and NORVIR therapy should be discontinued if a diagnosis of pancreatitis is made.
Allergic reactions including urticaria, mild skin eruptions, bronchospasm, and angioedema have been reported. Cases of anaphylaxis, toxic epidermal necrolysis (TEN), and Stevens-Johnson syndrome have also been reported. Discontinue treatment if severe reactions develop.
Ritonavir prolongs the PR interval in some patients. Post marketing cases of second or third degree atrioventricular block have been reported in patients.
NORVIR should be used with caution in patients with underlying structural heart disease, preexisting conduction system abnormalities, ischemic heart disease, cardiomyopathies, as these patients may be at increased risk for developing cardiac conduction abnormalities.
The impact on the PR interval of co-administration of ritonavir with other drugs that prolong the PR interval (including calcium channel blockers, beta-adrenergic blockers, digoxin and atazanavir) has not been evaluated. As a result, co-administration of ritonavir with these drugs should be undertaken with caution, particularly with those drugs metabolized by CYP3A. Clinical monitoring is recommended [see Drug Interactions (7) and Clinical Pharmacology (12.3)].
Treatment with NORVIR therapy alone or in combination with saquinavir has resulted in substantial increases in the concentration of total cholesterol and triglycerides [see Adverse Reactions (6.1)]. Triglyceride and cholesterol testing should be performed prior to initiating NORVIR therapy and at periodic intervals during therapy. Lipid disorders should be managed as clinically appropriate, taking into account any potential drug-drug interactions with NORVIR and HMG CoA reductase inhibitors [see Contraindications (4)and Drug Interactions (7)].
New onset diabetes mellitus, exacerbation of pre-existing diabetes mellitus, and hyperglycemia have been reported during postmarketing surveillance in HIV-infected patients receiving protease inhibitor therapy. Some patients required either initiation or dose adjustments of insulin or oral hypoglycemic agents for treatment of these events. In some cases, diabetic ketoacidosis has occurred. In those patients who discontinued protease inhibitor therapy, hyperglycemia persisted in some cases. Because these events have been reported voluntarily during clinical practice, estimates of frequency cannot be made and a causal relationship between protease inhibitor therapy and these events has not been established. Consider monitoring for hyperglycemia, new onset diabetes mellitus, or an exacerbation of diabetes mellitus in patients treated with NORVIR.
Immune reconstitution syndrome has been reported in HIV-infected patients treated with combination antiretroviral therapy, including NORVIR. During the initial phase of combination antiretroviral treatment, patients whose immune system responds may develop an inflammatory response to indolent or residual opportunistic infections (such as Mycobacterium avium infection, cytomegalovirus, Pneumocystis jiroveci pneumonia, or tuberculosis), which may necessitate further evaluation and treatment.
Autoimmune disorders (such as Graves’ disease, polymyositis, and Guillain-Barré syndrome) have also been reported to occur in the setting of immune reconstitution, however, the time to onset is more variable, and can occur many months after initiation of treatment.
Redistribution/accumulation of body fat including central obesity, dorsocervical fat enlargement (buffalo hump), peripheral wasting, facial wasting, breast enlargement, and "cushingoid appearance" have been observed in patients receiving antiretroviral therapy. The mechanism and long-term consequences of these events are currently unknown. A causal relationship has not been established.
There have been reports of increased bleeding, including spontaneous skin hematomas and hemarthrosis, in patients with hemophilia type A and B treated with protease inhibitors. In some patients additional factor VIII was given. In more than half of the reported cases, treatment with protease inhibitors was continued or reintroduced. A causal relationship between protease inhibitor therapy and these events has not been established.
Varying degrees of cross-resistance among protease inhibitors have been observed. Continued administration of ritonavir 600 mg twice daily following loss of viral suppression may increase the likelihood of cross-resistance to other protease inhibitors [see Microbiology (12.4)].
Ritonavir has been shown to increase triglycerides, cholesterol, SGOT (AST), SGPT (ALT), GGT, CPK, and uric acid. Appropriate laboratory testing should be performed prior to initiating NORVIR therapy and at periodic intervals or if any clinical signs or symptoms occur during therapy.
The following adverse reactions are discussed in greater detail in other sections of the labeling.
When co-administering NORVIR with other protease inhibitors, see the full prescribing information for that protease inhibitor including adverse reactions.
Because clinical trials are conducted under widely varying conditions, adverse reactions rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
Adverse Reactions in Adults
The safety of NORVIR alone and in combination with other antiretroviral agents was studied in 1,755 adult patients. Table 2 lists treatment-emergent Adverse Reactions (with possible or probable relationship to study drug) occurring in greater than or equal to 1% of adult patients receiving NORVIR in combined Phase II/IV studies.
The most frequently reported adverse drug reactions among patients receiving NORVIR alone or in combination with other antiretroviral drugs were gastrointestinal (including diarrhea, nausea, vomiting, abdominal pain (upper and lower)), neurological disturbances (including paresthesia and oral paresthesia), rash, and fatigue/asthenia.
Laboratory Abnormalities in Adults
Table 3 shows the percentage of adult patients who developed marked laboratory abnormalities.
Adverse Reactions in Pediatric Patients
NORVIR has been studied in 265 pediatric patients greater than 1 month to 21 years of age. The adverse event profile observed during pediatric clinical trials was similar to that for adult patients.
Vomiting, diarrhea, and skin rash/allergy were the only drug-related clinical adverse events of moderate to severe intensity observed in greater than or equal to 2% of pediatric patients enrolled in NORVIR clinical trials.
Laboratory Abnormalities in Pediatric Patients
The following Grade 3-4 laboratory abnormalities occurred in greater than 3% of pediatric patients who received treatment with NORVIR either alone or in combination with reverse transcriptase inhibitors: neutropenia (9%), hyperamylasemia (7%), thrombocytopenia (5%), anemia (4%), and elevated AST (3%).
The following adverse events (not previously mentioned in the labeling) have been reported during post-marketing use of NORVIR. Because these reactions are reported voluntarily from a population of unknown size, it is not possible to reliably estimate their frequency or establish a causal relationship to NORVIR exposure.
Body as a Whole
Dehydration, usually associated with gastrointestinal symptoms, and sometimes resulting in hypotension, syncope, or renal insufficiency has been reported. Syncope, orthostatic hypotension, and renal insufficiency have also been reported without known dehydration.
Co-administration of ritonavir with ergotamine or dihydroergotamine has been associated with acute ergot toxicity characterized by vasospasm and ischemia of the extremities and other tissues including the central nervous system.
First-degree AV block, second-degree AV block, third-degree AV block, right bundle branch block have been reported [see Warnings and Precautions (5.6)].
Cardiac and neurologic events have been reported when ritonavir has been co-administered with disopyramide, mexiletine, nefazodone, fluoxetine, and beta blockers. The possibility of drug interaction cannot be excluded.
Cushing's syndrome and adrenal suppression have been reported when ritonavir has been co-administered with fluticasone propionate or budesonide.
There have been postmarketing reports of seizure. Also, see Cardiovascular System.
Skin and subcutaneous tissue disorders
Toxic epidermal necrolysis (TEN) has been reported.
When co-administering NORVIR with other protease inhibitors (atazanavir, darunavir, fosamprenavir, saquinavir, and tipranavir), see the full prescribing information for that protease inhibitor including important information for drug interactions.
Ritonavir is an inhibitor of cytochrome P450 3A (CYP3A) and may increase plasma concentrations of agents that are primarily metabolized by CYP3A. Agents that are extensively metabolized by CYP3A and have high first pass metabolism appear to be the most susceptible to large increases in AUC (greater than 3-fold) when co-administered with ritonavir. Thus, co-administration of NORVIR with drugs highly dependent on CYP3A for clearance and for which elevated plasma concentrations are associated with serious and/or life-threatening events is contraindicated. Co-administration with other CYP3A substrates may require a dose adjustment or additional monitoring as shown in Table 4.
Ritonavir also inhibits CYP2D6 to a lesser extent. Co-administration of substrates of CYP2D6 with ritonavir could result in increases (up to 2-fold) in the AUC of the other agent, possibly requiring a proportional dosage reduction. Ritonavir also appears to induce CYP3A, CYP1A2, CYP2C9, CYP2C19, and CYP2B6 as well as other enzymes, including glucuronosyl transferase.
These examples are a guide and not considered a comprehensive list of all possible drugs that may interact with ritonavir. The healthcare provider should consult appropriate references for comprehensive information.
Table 4 provides a list of established or potentially clinically significant drug interactions. Alteration in dose or regimen may be recommended based on drug interaction studies or predicted interaction [see Contraindications (4), Warnings and Precautions (5.1), and Clinical Pharmacology (12.3)] for magnitude of interaction.
Initiation of NORVIR in patients taking quetiapine:
Consider alternative antiretroviral therapy to avoid increases in quetiapine exposures. If coadministration is necessary, reduce the quetiapine dose to 1/6 of the current dose and monitor for quetiapine-associated adverse reactions. Refer to the quetiapine prescribing information for recommendations on adverse reaction monitoring.
Initiation of quetiapine in patients taking NORVIR:
Co-administration of bosentan in patients on ritonavir:
In patients who have been receiving ritonavir for at least 10 days, start bosentan at 62.5 mg once daily or every other day based upon individual tolerability.
Co-administration of ritonavir in patients on bosentan:
Discontinue use of bosentan at least 36 hours prior to initiation of ritonavir.
Co-administration of ADCIRCA in patients on ritonavir:
In patients receiving ritonavir for at least one week, start ADCIRCA at 20 mg once daily. Increase to 40 mg once daily based upon individual tolerability.
Co-administration of ritonavir in patients on ADCIRCA:
Avoid use of ADCIRCA during the initiation of ritonavir. Stop ADCIRCA at least 24 hours prior to starting ritonavir. After at least one week following the initiation of ritonavir, resume ADCIRCA at 20 mg once daily. Increase to 40 mg once daily based upon individual tolerability.
Use of PDE5 inhibitors for the treatment of erectile dysfunction:
It is recommended not to exceed the following doses:
When co-administering NORVIR with other protease inhibitors, see the full prescribing information for the co-administered protease inhibitor including important information for use in special populations.
Pregnancy Exposure Registry
There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to NORVIR during pregnancy. Healthcare providers are encouraged to register patients by calling the Antiretroviral Pregnancy Registry (APR) at 1-800-258-4263.
Prospective pregnancy data from the Antiretroviral Pregnancy Registry (APR) are not sufficient to adequately assess the risk of birth defects or miscarriage. Available data from the APR show no difference in the rate of overall birth defects for ritonavir compared to the background rate for major birth defects of 2.7% in the U.S. reference population of the Metropolitan Atlanta Congenital Defects Program (MACDP) [see Data].
In animal reproduction studies, no evidence of adverse developmental outcomes was observed with oral administration of ritonavir to pregnant rats and rabbits. During organogenesis in the rat and rabbit, systemic exposure (AUC) was approximately 1/3 lower than human exposure at the recommended daily dose. In the rat pre- and post-natal developmental study, maternal systemic exposure to ritonavir was approximately 1/2 of the exposure in humans at the recommended daily dose, based on a body surface area conversion factor [see Data].
NORVIR oral solution is not recommended during pregnancy because there is no known safe level of ethanol exposure during pregnancy [see Clinical Considerations, Dosage and Administration (2.3) and Warnings and Precautions (5.2)].
The background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively.
Dose Adjustments During Pregnancy and the Postpartum Period
NORVIR oral solution contains approx. 43% ethanol (v/v) and approx. 27% (w/v) propylene glycol and is not recommended during pregnancy because there is no known safe level of ethanol exposure during pregnancy [see Dosage and Administration (2.3) and Warnings and Precautions (5.2)].
Based on prospective reports to the APR of approximately 6100 live births following exposure to ritonavir-containing regimens (including over 2800 live births exposed in the first trimester and over 3200 live births exposed in the second and third trimesters), there was no difference in the rate of overall birth defects for ritonavir compared with the background birth defect rate of 2.7% in the U.S. reference population of the MACDP. The prevalence of birth defects in live births was 2.3% (95% CI: 1.7%-2.9%) following first-trimester exposure to ritonavir-containing regimens and 2.9% (95% CI: 2.3%-3.5%) following second and third trimester exposure to ritonavir-containing regimens.
While placental transfer of ritonavir and fetal ritonavir concentrations are generally low, detectable levels have been observed in cord blood samples and neonate hair.
Ritonavir was administered orally to pregnant rats (at 0, 15, 35, and 75 mg/kg/day) and rabbits (at 0, 25, 50, and 110 mg/kg/day) during organogenesis (on gestation days 6 through 17 and 6 through 19, respectively). No evidence of teratogenicity due to ritonavir was observed in rats and rabbits at doses producing systemic exposures (AUC) equivalent to approximately 1/3 lower than human exposure at the recommended daily dose. Developmental toxicity observed in rats (early resorptions, decreased fetal body weight and ossification delays and developmental variations) occurred at a maternally toxic dose, at an exposure equivalent to approximately 1/3 lower than human exposure at the recommended daily dose. A slight increase in the incidence of cryptorchidism was also noted in rats (at a maternally toxic dose) at an exposure approximately 1/5 lower than human exposure at the recommended daily dose. Developmental toxicity was observed in rabbits (resorptions, decreased litter size and decreased fetal weights) at maternally toxic doses approximately 1.8 times higher than the recommended daily dose, based on a body surface area conversion factor. In pre-and postnatal development study in rats, ritonavir was administered at doses of 0, 15, 35, and 60 mg/kg/day from gestation day 6 through postnatal day 20. At doses of 60 mg/kg/day, no developmental toxicity was noted with ritonavir dosage equivalent to 1/2 of the recommended daily dose, based on a body surface area conversion factor.
The Centers for Disease Control and Prevention recommend that HIV-infected mothers not breastfeed their infants to avoid risking postnatal transmission of HIV.
Limited published data reports that ritonavir is present in human milk.
There is no information on the effects of ritonavir on the breastfed infant or the effects of the drug on milk production. Because of the potential for (1) HIV transmission (in HIV-negative infants), (2) developing viral resistance (in HIV-positive infants) and (3) serious adverse reactions in a breastfed infant, instruct mothers not to breastfeed if they are receiving NORVIR.
Use of NORVIR may reduce the efficacy of combined hormonal contraceptives. Advise patients using combined hormonal contraceptives to use an effective alternative contraceptive method or an additional barrier method of contraception [see Drug Interactions (7.2)].
In HIV-infected patients age greater than 1 month to 21 years, the antiviral activity and adverse event profile seen during clinical trials and through postmarketing experience were similar to that for adult patients.
Clinical studies of NORVIR did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal or cardiac function, and of concomitant disease or other drug therapy.
No dose adjustment of ritonavir is necessary for patients with either mild (Child-Pugh Class A) or moderate (Child-Pugh Class B) hepatic impairment. No pharmacokinetic or safety data are available regarding the use of ritonavir in subjects with severe hepatic impairment (Child-Pugh Class C), therefore, ritonavir is not recommended for use in patients with severe hepatic impairment [see Warnings and Precautions (5.3), Clinical Pharmacology (12.3)].
Acute Overdosage - Human Overdose Experience
Human experience of acute overdose with NORVIR is limited. One patient in clinical trials took NORVIR 1500 mg per day for two days. The patient reported paresthesias which resolved after the dose was decreased. A post-marketing case of renal failure with eosinophilia has been reported with ritonavir overdose.
The approximate lethal dose was found to be greater than 20 times the related human dose in rats and 10 times the related human dose in mice.
Management of Overdosage
NORVIR oral solution contains approx. 43% ethanol (v/v) and approx. 27% (w/v) propylene glycol. Ingestion of the product over the recommended dose by a young child could result in significant toxicity and could potentially be lethal.
Treatment of overdose with NORVIR consists of general supportive measures including monitoring of vital signs and observation of the clinical status of the patient. There is no specific antidote for overdose with NORVIR. If indicated, elimination of unabsorbed drug should be achieved by gastric lavage; usual precautions should be observed to maintain the airway. Administration of activated charcoal may also be used to aid in removal of unabsorbed drug. Since ritonavir is extensively metabolized by the liver and is highly protein bound, dialysis is unlikely to be beneficial in significant removal of the drug. However, dialysis can remove both ethanol and propylene glycol in the case of overdose with ritonavir oral solution. A Certified Poison Control Center should be consulted for up-to-date information on the management of overdose with NORVIR.
NORVIR (ritonavir) is an inhibitor of HIV protease with activity against the Human Immunodeficiency Virus (HIV).
Ritonavir is chemically designated as 10-Hydroxy-2-methyl-5-(1-methylethyl)-1- [2-(1-methylethyl)-4-thiazolyl]-3,6-dioxo-8,11-bis(phenylmethyl)-2,4,7,12- tetraazatridecan-13-oic acid, 5-thiazolylmethyl ester, [5S-(5R*,8R*,10R*,11R*)]. Its molecular formula is C37H48N6O5S2, and its molecular weight is 720.95. Ritonavir has the following structural formula:
Ritonavir is a white-to-light-tan powder. Ritonavir has a bitter metallic taste. It is freely soluble in methanol and ethanol, soluble in isopropanol and practically insoluble in water.
NORVIR tablets are available for oral administration in a strength of 100 mg ritonavir with the following inactive ingredients: copovidone, anhydrous dibasic calcium phosphate, sorbitan monolaurate, colloidal silicon dioxide, and sodium stearyl fumarate. The following are the ingredients in the film coating: hypromellose, titanium dioxide, polyethylene glycol 400, hydroxypropyl cellulose, talc, polyethylene glycol 3350, colloidal silicon dioxide, and polysorbate 80.
NORVIR oral solution is available for oral administration as 80 mg per mL of ritonavir in a peppermint and caramel flavored vehicle. Each 8-ounce bottle contains 19.2 grams of ritonavir. NORVIR oral solution also contains ethanol, water, polyoxyl 35 castor oil, propylene glycol, anhydrous citric acid to adjust pH, saccharin sodium, peppermint oil, creamy caramel flavoring, and FD&C Yellow No. 6. NORVIR oral solution contains approximately 43% (v/v) ethanol and approximately 27% (w/v) propylene glycol.
NORVIR oral powder is beige/pale yellow to yellow and is available for oral administration as a packet containing 100 mg of ritonavir with the following inactive ingredients: copovidone, sorbitan monolaurate, and colloidal silicon dioxide.
Ritonavir is an antiretroviral drug [see Microbiology (12.4)].
QTcF interval was evaluated in a randomized, placebo and active (moxifloxacin 400 mg once-daily) controlled crossover study in 45 healthy adults, with 10 measurements over 12 hours on Day 3. The maximum mean (95% upper confidence bound) time-matched difference in QTcF from placebo after baseline correction was 5.5 (7.6) milliseconds (msec) for 400 mg twice-daily ritonavir. Ritonavir 400 mg twice daily resulted in Day 3 ritonavir exposure that was approximately 1.5 fold higher than observed with ritonavir 600 mg twice-daily dose at steady state.
PR interval prolongation was also noted in subjects receiving ritonavir in the same study on Day 3. The maximum mean (95% confidence interval) difference from placebo in the PR interval after baseline correction was 22 (25) msec for 400 mg twice-daily ritonavir [see Warnings and Precautions (5.6)].
The pharmacokinetics of ritonavir have been studied in healthy volunteers and HIV-infected patients (CD4 greater than or equal to 50 cells per μL). See Table 5 for ritonavir pharmacokinetic characteristics.
The absolute bioavailability of ritonavir has not been determined. After a 600 mg dose of oral solution, peak concentrations of ritonavir were achieved approximately 2 hours and 4 hours after dosing under fasting and non-fasting (514 KCal; 9% fat, 12% protein, and 79% carbohydrate) conditions, respectively.
NORVIR tablets are not bioequivalent to NORVIR capsules. Under moderate fat conditions (857 kcal; 31% fat, 13% protein, 56% carbohydrates), when a single 100 mg NORVIR dose was administered as a tablet compared with a capsule, AUC(0- ∞) met equivalence criteria but mean Cmax was increased by 26% (92.8% confidence intervals: ↑15 -↑39%).
No information is available comparing NORVIR tablets to NORVIR capsules under fasting conditions.
After administration of a single 100 mg dose under fed conditions (617 Kcal, 29% calories from fat), NORVIR oral powder demonstrated comparable bioavailability to the oral solution.
Effect of Food on Oral Absorption
The bioavailability of NORVIR tablet, oral solution, and oral powder is decreased under fed conditions as compared to fasted conditions.
Following the administration of a 100 mg tablet dose of NORVIR, Cmax and AUCinf of ritonavir were decreased by 21-23% under moderate fat (857 Kcal, 30% from fat) or high fat conditions (917 Kcal, 60% calories from fat) relative to fasting conditions.
Following the administration of a 600 mg dose NORVIR oral solution, Cmax and AUCinf of ritonavir were decreased by 23% and 7%, respectively, under nonfasting conditions (514 Kcal, 10% from fat) relative to fasting conditions. Dilution of the oral solution, within one hour of administration, with 240 mL of chocolate milk, Advera® or Ensure® did not significantly affect the extent and rate of ritonavir absorption.
Following the administration of a 100 mg dose of NORVIR oral powder, Cmax and AUCinf of ritonavir were decreased by 23-49% under moderate fat (617 Kcal, 29% calories from fat) or high fat conditions (917 Kcal, 60% calories from fat) relative to fasting conditions.
Nearly all of the plasma radioactivity after a single oral 600 mg dose of 14C-ritonavir oral solution (n = 5) was attributed to unchanged ritonavir. Five ritonavir metabolites have been identified in human urine and feces. The isopropylthiazole oxidation metabolite (M-2) is the major metabolite and has antiviral activity similar to that of parent drug; however, the concentrations of this metabolite in plasma are low. In vitro studies utilizing human liver microsomes have demonstrated that cytochrome P450 3A (CYP3A) is the major isoform involved in ritonavir metabolism, although CYP2D6 also contributes to the formation of M–2.
In a study of five subjects receiving a 600 mg dose of 14C-ritonavir oral solution, 11.3 ± 2.8% of the dose was excreted into the urine, with 3.5 ± 1.8% of the dose excreted as unchanged parent drug. In that study, 86.4 ± 2.9% of the dose was excreted in the feces with 33.8 ± 10.8% of the dose excreted as unchanged parent drug. Upon multiple dosing, ritonavir accumulation is less than predicted from a single dose possibly due to a time and dose-related increase in clearance.
Gender, Race and Age
No age-related pharmacokinetic differences have been observed in adult patients (18 to 63 years). Ritonavir pharmacokinetics have not been studied in older patients.
A study of ritonavir pharmacokinetics in healthy males and females showed no statistically significant differences in the pharmacokinetics of ritonavir. Pharmacokinetic differences due to race have not been identified.
Steady-state pharmacokinetics were evaluated in 37 HIV-infected patients ages 2 to 14 years receiving doses ranging from 250 mg per m2 twice-daily to 400 mg per m2 twice-daily in PACTG Study 310, and in 41 HIV-infected patients ages 1 month to 2 years at doses of 350 and 450 mg per m2 twice-daily in PACTG Study 345. Across dose groups, ritonavir steady-state oral clearance (CL/F/m2) was approximately 1.5 to 1.7 times faster in pediatric patients than in adult subjects. Ritonavir concentrations obtained after 350 to 400 mg per m2 twice-daily in pediatric patients greater than 2 years were comparable to those obtained in adults receiving 600 mg (approximately 330 mg per m2) twice-daily. The following observations were seen regarding ritonavir concentrations after administration with 350 or 450 mg per m2 twice-daily in children less than 2 years of age. Higher ritonavir exposures were not evident with 450 mg per m2 twice-daily compared to the 350 mg per m2 twice-daily. Ritonavir trough concentrations were somewhat lower than those obtained in adults receiving 600 mg twice-daily. The area under the ritonavir plasma concentration time curve and trough concentrations obtained after administration with 350 or 450 mg per m2 twice-daily in children less than 2 years were approximately 16% and 60% lower, respectively, than that obtained in adults receiving 600 mg twice daily.
Ritonavir pharmacokinetics have not been studied in patients with renal impairment, however, since renal clearance is negligible, a decrease in total body clearance is not expected in patients with renal impairment.
Dose-normalized steady-state ritonavir concentrations in subjects with mild hepatic impairment (400 mg twice-daily, n = 6) were similar to those in control subjects dosed with 500 mg twice-daily. Dose-normalized steady-state ritonavir exposures in subjects with moderate hepatic impairment (400 mg twice-daily, n= 6) were about 40% lower than those in subjects with normal hepatic function (500 mg twice-daily, n = 6). Protein binding of ritonavir was not statistically significantly affected by mild or moderately impaired hepatic function. No dose adjustment is recommended in patients with mild or moderate hepatic impairment. However, health care providers should be aware of the potential for lower ritonavir concentrations in patients with moderate hepatic impairment and should monitor patient response carefully. Ritonavir has not been studied in patients with severe hepatic impairment.
Based on evaluation of the published literature, ritonavir exposures are reduced during pregnancy relative to postpartum.
[see also Contraindications (4), Warnings and Precautions (5.1), and Drug Interactions (7)]
Table 6 and Table 7 summarize the effects on AUC and Cmax, with 95% confidence intervals (95% CI), of co-administration of ritonavir with a variety of drugs. For information about clinical recommendations see Table 4 in Drug Interactions (7).
Mechanism of Action
Ritonavir is a peptidomimetic inhibitor of the HIV-1 protease. Inhibition of HIV protease renders the enzyme incapable of processing the Gag-Pol polyprotein precursor which leads to production of non-infectious immature HIV particles.
Antiviral Activity in Cell Culture
The activity of ritonavir was assessed in acutely infected lymphoblastoid cell lines and in peripheral blood lymphocytes. The concentration of drug that inhibits 50% (EC50) value of viral replication ranged from 3.8 to 153 nM depending upon the HIV-1 isolate and the cells employed. The average EC50 value for low passage clinical isolates was 22 nM (n = 13). In MT4 cells, ritonavir demonstrated additive effects against HIV-1 in combination with either didanosine (ddI) or zidovudine (ZDV). Studies which measured cytotoxicity of ritonavir on several cell lines showed that greater than 20 microM was required to inhibit cellular growth by 50% resulting in a cell culture therapeutic index of at least 1000.
HIV-1 isolates with reduced susceptibility to ritonavir have been selected in cell culture. Genotypic analysis of these isolates showed mutations in the HIV-1 protease gene leading to amino acid substitutions I84V, V82F, A71V, and M46I. Phenotypic (n = 18) and genotypic (n = 48) changes in HIV-1 isolates from selected patients treated with ritonavir were monitored in phase I/II trials over a period of 3 to 32 weeks. Substitutions associated with the HIV–1 viral protease in isolates obtained from 43 patients appeared to occur in a stepwise and ordered fashion at positions V82A/F/T/S, I54V, A71V/T, and I36L, followed by combinations of substitutions at an additional 5 specific amino acid positions (M46I/L, K20R, I84V, L33F and L90M). Of 18 patients for whom both phenotypic and genotypic analysis were performed on free virus isolated from plasma, 12 showed reduced susceptibility to ritonavir in cell culture. All 18 patients possessed one or more substitutions in the viral protease gene. The V82A/F substitution appeared to be necessary but not sufficient to confer phenotypic resistance. Phenotypic resistance was defined as a greater than or equal to 5-fold decrease in viral sensitivity in cell culture from baseline.
Cross-Resistance to Other Antiretrovirals
Among protease inhibitors variable cross-resistance has been recognized. Serial HIV-1 isolates obtained from six patients during ritonavir therapy showed a decrease in ritonavir susceptibility in cell culture but did not demonstrate a concordant decrease in susceptibility to saquinavir in cell culture when compared to matched baseline isolates. However, isolates from two of these patients demonstrated decreased susceptibility to indinavir in cell culture (8-fold). Isolates from 5 patients were also tested for cross-resistance to amprenavir and nelfinavir; isolates from 3 patients had a decrease in susceptibility to nelfinavir (6- to 14-fold), and none to amprenavir. Cross-resistance between ritonavir and reverse transcriptase inhibitors is unlikely because of the different enzyme targets involved. One ZDV-resistant HIV-1 isolate tested in cell culture retained full susceptibility to ritonavir.
Carcinogenicity studies in mice and rats have been carried out on ritonavir. In male mice, at levels of 50, 100 or 200 mg per kg per day, there was a dose dependent increase in the incidence of both adenomas and combined adenomas and carcinomas in the liver. Based on AUC measurements, the exposure at the high dose was approximately 0.3-fold for males that of the exposure in humans with the recommended therapeutic dose (600 mg twice-daily). There were no carcinogenic effects seen in females at the dosages tested. The exposure at the high dose was approximately 0.6-fold for the females that of the exposure in humans. In rats dosed at levels of 7, 15 or 30 mg per kg per day there were no carcinogenic effects. In this study, the exposure at the high dose was approximately 6% that of the exposure in humans with the recommended therapeutic dose. Based on the exposures achieved in the animal studies, the significance of the observed effects is not known.
However, ritonavir was found to be negative for mutagenic or clastogenic activity in a battery of in vitro and in vivo assays including the Ames bacterial reverse mutation assay using S. typhimurium and E. coli, the mouse lymphoma assay, the mouse micronucleus test and chromosomal aberration assays in human lymphocytes.
Impairment of Fertility
Ritonavir produced no effects on fertility in rats at drug exposures approximately 40% (male) and 60% (female) of that achieved with the proposed therapeutic dose. Higher dosages were not feasible due to hepatic toxicity.
The activity of NORVIR as monotherapy or in combination with nucleoside reverse transcriptase inhibitors has been evaluated in 1446 patients enrolled in two double-blind, randomized trials.
Study 247 was a randomized, double-blind trial (with open-label follow-up) conducted in HIV-infected patients with at least nine months of prior antiretroviral therapy and baseline CD4 cell counts less than or equal to 100 cells per μL. NORVIR 600 mg twice-daily or placebo was added to each patient's baseline antiretroviral therapy regimen, which could have consisted of up to two approved antiretroviral agents. The study accrued 1,090 patients, with mean baseline CD4 cell count at study entry of 32 cells per μL. After the clinical benefit of NORVIR therapy was demonstrated, all patients were eligible to switch to open-label NORVIR for the duration of the follow-up period. Median duration of double-blind therapy with NORVIR and placebo was 6 months. The median duration of follow-up through the end of the open-label phase was 13.5 months for patients randomized to NORVIR and 14 months for patients randomized to placebo.
The cumulative incidence of clinical disease progression or death during the double-blind phase of Study 247 was 26% for patients initially randomized to NORVIR compared to 42% for patients initially randomized to placebo. This difference in rates was statistically significant.
Cumulative mortality through the end of the open-label follow-up phase for patients enrolled in Study 247 was 18% (99/543) for patients initially randomized to NORVIR compared to 26% (142/547) for patients initially randomized to placebo. This difference in rates was statistically significant. However, since the analysis at the end of the open-label phase includes patients in the placebo arm who were switched from placebo to NORVIR therapy, the survival benefit of NORVIR cannot be precisely estimated.
During the double-blind phase of Study 247, CD4 cell counts increases from baseline for patients randomized to NORVIR at Week 2 and Week 4 were observed. From Week 4 and through Week 24, mean CD4 cell counts for patients randomized to NORVIR appeared to plateau. In contrast, there was no apparent change in mean CD4 cell counts for patients randomized to placebo at any visit between baseline and Week 24 of the double-blind phase of Study 247.
In Study 245, 356 antiretroviral-naive HIV-infected patients (mean baseline CD4 = 364 cells per μL) were randomized to receive either NORVIR 600 mg twice-daily, zidovudine 200 mg three-times-daily, or a combination of these drugs.
During the double-blind phase of study 245, greater mean CD4 cell count increases were observed from baseline to Week 12 in the NORVIR-containing arms compared to the zidovudine arms. Mean CD4 cell count changes subsequently appeared to plateau through Week 24 in the NORVIR arm, whereas mean CD4 cell counts gradually diminished through Week 24 in the zidovudine and NORVIR plus zidovudine arms.
Greater mean reductions in plasma HIV-1 RNA levels were observed from baseline to Week 2 for the NORVIR-containing arms compared to the zidovudine arm. After Week 2 and through Week 24, mean plasma HIV-1 RNA levels either remained stable in the NORVIR and zidovudine arms or gradually rebounded toward baseline in the NORVIR plus zidovudine arm.
The package sizes, strengths, and storage and handling recommendations for NORVIR (ritonavir) tablets, oral solution and oral powder are shown in the table below.
Advise the patient to read the FDA-approved patient labeling (Patient Information and Instructions for Use)
General Administration Information [see Dosage and Administration (2)]:
Pre-existing liver disease including Hepatitis B or C can worsen with use of NORVIR. This can be seen as worsening of transaminase elevations or hepatic decompensation. Advise patients that their liver function tests will need to be monitored closely especially during the first several months of NORVIR treatment and that they should notify their healthcare provider if they develop the signs and symptoms of worsening liver disease including loss of appetite, abdominal pain, jaundice, and itchy skin [see Warnings and Precautions (5.3)].
Pancreatitis, including some fatalities, has been observed in patients receiving NORVIR therapy. Advise patients to notify their healthcare provider of signs and symptoms (nausea, vomiting, and abdominal pain) that might be suggestive of pancreatitis [see Warnings and Precautions (5.4)].
Skin rashes ranging in severity from mild to Stevens-Johnson syndrome have been reported in patients receiving NORVIR. Advise patients to contact their healthcare provider if they develop a rash while taking NORVIR [see Warnings and Precautions (5.5)].
PR Interval Prolongation
NORVIR may produce changes in the electrocardiogram (e.g., PR prolongation). Advise patients to consult their healthcare provider if they experience symptoms such as dizziness, lightheadedness, abnormal heart rhythm or loss of consciousness [see Warnings and Precautions (5.6)].
Advise patients that treatment with NORVIR therapy can result in substantial increases in the concentration of total cholesterol and triglycerides [see Warnings and Precautions (5.7)].
Advise patients that new onset of diabetes or exacerbation of pre-existing diabetes mellitus, and hyperglycemia have been reported and to notify their healthcare provider if they develop the signs and symptoms of diabetes mellitus including frequent urination, excessive thirst, extreme hunger or unusual weight loss and/or an increased blood sugar while on NORVIR as they may require a change in their diabetes treatment or new treatment [see Warnings and Precautions (5.8)].
Immune Reconstitution Syndrome
Advise patients that immune reconstitution syndrome has been reported in HIV-infected patients treated with combination antiretroviral therapy, including NORVIR [see Warnings and Precautions (5.9)].
Advise patients that redistribution or accumulation of body fat may occur in patients receiving antiretroviral therapy and that the cause and long term health effects of these conditions are not known at this time [see Warnings and Precautions (5.10)].
Patients with Hemophilia
Advise patients with hemophilia that they may experience increased bleeding when treated with protease inhibitors such as NORVIR [see Warnings and Precautions (5.11)].
NORVIR Oral Solution Not Recommended During Pregnancy
Advise pregnant women that use of NORVIR oral solution during pregnancy is not recommended due to its ethanol content [see Dosage and Administration (2.3) and Use in Specific Population (8.1)].
Pregnancy Exposure Registry
Inform patients that there is an antiretroviral pregnancy registry that monitors fetal outcomes of pregnant women exposed to NORVIR [see Use in Specific Populations (8.1)].
Instruct women with HIV-1 infection not to breastfeed because HIV-1 can be passed to the baby in breast milk [see Use in Specific Populations (8.2)].
NORVIR tablets and oral solution are manufactured by:AbbVie Inc. North Chicago, IL 60064 USA
NORVIR oral powder is manufactured for:AbbVie Inc. North Chicago, IL 60064 USA
© 2019 AbbVie Inc. All rights reserved.03-C081
How should I take NORVIR?See the detailed Instructions for Use for information about how to give or take a dose of NORVIR oral powder.
How should I store NORVIR?
Store NORVIR tablets:
Store NORVIR oral solution:
Store NORVIR oral powder:
Keep NORVIR and all medicines out of the reach of children.
What are the ingredients in NORVIR?
Active ingredient: ritonavir
NORVIR tablet: copovidone, anhydrous dibasic calcium phosphate, sorbitan monolaurate, colloidal silicon dioxide, and sodium stearyl fumarate. The film coating contains: hypromellose, titanium dioxide, polyethylene glycol 400, hydroxypropyl cellulose, talc, polyethylene glycol 3350, colloidal silicon dioxide, and polysorbate 80.
NORVIR oral solution: ethanol, water, polyoxyl 35 castor oil, propylene glycol, anhydrous citric acid to adjust pH, saccharin sodium, peppermint oil, creamy caramel flavoring, and FD&C Yellow No. 6.
NORVIR oral powder: copovidone, sorbitan monolaurate, and colloidal silicon dioxide.
NORVIR tablets and NORVIR oral solution are manufactured by: AbbVie Inc., North Chicago, IL 60064 USA
NORVIR oral powder is manufactured for: AbbVie Inc., North Chicago, IL 60064 USA
For more information, call 1-800-633-9110.
The brands listed are trademarks of their respective owners and are not trademarks of AbbVie Inc. The makers of these brands are not affiliated with and do not endorse AbbVie Inc. or its products. © 2019 AbbVie Inc. All rights reserved.
Instructions for UseNORVIR®(ritonavir)oral powder
Read these Instructions for Use before you give or take a dose of NORVIR oral powder for the first time and every time you get a new prescription. There may be new information. Talk to your healthcare provider if you have any questions.
For more information about NORVIR oral powder see the Patient Information section of the Prescribing Information.
Items included in the NORVIR oral powder carton
Gather items to prepare your dose
If your dose is 100 mg or 200 mg: You will need 1 packet of NORVIR oral powder for 100 mg and 2 packets of NORVIR oral powder for 200 mg.
Note: If your healthcare provider prescribes a dose of NORVIR oral powder that is not 100 mg or 200 mg, your healthcare provider should tell you how to prepare your dose. Be sure to prepare your dose exactly as your healthcare provider tells you.
You will also need the following items to prepare your dose of NORVIR oral powder with food (not included in the NORVIR oral powder carton):
If you are preparing a dose of NORVIR oral powder in liquid, you will also need the following items (not included in your NORVIR oral powder carton):
The instructions below show the dose being prepared with food, but if you are using liquid you can swap the food for a liquid.
This Instructions for Use has been approved by the U.S. Food and Drug Administration.
Manufactured by: NORVIR Oral Powder is manufactured for: AbbVie Inc., North Chicago, IL 60064 USA.
Issued: September 2017
NOTE: These photos can be used only for identification by shape, color, and imprint. They do not depict actual or relative size.
The product samples shown here have been supplied by the manufacturer and reproduced in full color by PDR as a quick-reference identification aid. While every effort has been made to assure accurate reproduction, please remember that any visual identification should be considered preliminary. In cases of poisoning or suspected over dosage, the drug's identity should be verified by chemical analysis.