Clarinex

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Clarinex

Classes

Second Generation Antihistamines

Administration
Oral Administration Oral Solid Formulations

Tablets: Swallow tablets whole, do not chew.
Disintegrating Tablets: Administer by placing on the tongue. The tablet will dissolve rapidly until it can be swallowed in the saliva. Food or water do not affect bioavailability.

Oral Liquid Formulations

Oral syrup (0.5 mg/mL): Measure dose using a calibrated oral syringe, cup, or dropper.

Adverse Reactions
Severe

anaphylactoid reactions / Rapid / 0-1.0
seizures / Delayed / Incidence not known

Moderate

erythema / Early / 0-3.0
hepatitis / Delayed / 0-1.0
edema / Delayed / 0-1.0
dyspnea / Early / 0-1.0
sinus tachycardia / Rapid / Incidence not known
hyperbilirubinemia / Delayed / Incidence not known
elevated hepatic enzymes / Delayed / Incidence not known
palpitations / Early / Incidence not known
dystonic reaction / Delayed / Incidence not known
involuntary movements / Delayed / Incidence not known

Mild

infection / Delayed / 3.1-21.2
diarrhea / Early / 0-19.7
fever / Early / 5.5-16.9
headache / Early / 14.0-14.0
irritability / Delayed / 0-12.1
cough / Delayed / 0-10.8
drowsiness / Early / 2.1-9.1
vomiting / Early / 0-6.1
fatigue / Early / 2.1-5.0
nausea / Early / 3.0-5.0
pharyngitis / Delayed / 3.0-4.5
rhinorrhea / Early / 0-4.5
anorexia / Delayed / 0-4.5
insomnia / Early / 0-4.5
dizziness / Early / 4.0-4.0
epistaxis / Delayed / 0-3.1
appetite stimulation / Delayed / 0-3.1
emotional lability / Early / 0-3.1
maculopapular rash / Early / 0-3.1
xerostomia / Early / 3.0-3.0
myalgia / Early / 2.1-3.0
dyspepsia / Early / 3.0-3.0
dysmenorrhea / Delayed / 2.1-2.1
pruritus / Rapid / 0-1.0
urticaria / Rapid / 0-1.0
rash / Early / 0-1.0
hyperactivity / Early / Incidence not known
restlessness / Early / Incidence not known

Common Brand Names

Clarinex, Clarinex RediTab

Dea Class

Rx

Description

Oral non-sedating, long acting second-generation antihistamine; the active metabolite of loratadine
Used to relieve symptoms associated with seasonal and perennial allergic rhinitis and used for chronic idiopathic urticaria
Does not cause QT prolongation

Dosage And Indications
For the management of symptoms of seasonal allergies or perennial allergies, including allergic rhinitis. Oral dosage (tablet) Adults

5 mg PO once daily.

Children and Adolescents 12 years and older

5 mg PO once daily.

Oral dosage (orally disintegrating tablet) Adults

5 mg PO once daily.

Children and Adolescents 12 years and older

5 mg PO once daily.

Children 6 to 11 years

2.5 mg PO once daily.

Oral dosage (oral solution) Adults

5 mg PO once daily.

Children and Adolescents 12 years and older

5 mg PO once daily.

Children 6 to 11 years

2.5 mg PO once daily.

Children 1 to 5 years

1.25 mg PO once daily. NOTE: Desloratadine is not FDA-approved for the treatment of seasonal allergic rhinitis in children less than 2 years.

Infants 6 months and older

1 mg PO once daily. NOTE: Desloratadine is not FDA-approved for the treatment of seasonal allergic rhinitis in infants.

For the management of symptoms of chronic idiopathic urticaria (e.g., relief of pruritus, reduction in the size and number of hives). Oral dosage (tablet) Adults

5 mg PO once daily.

Children and Adolescents 12 years and older

5 mg PO once daily.

Oral dosage (orally disintegrating tablet) Adults

5 mg PO once daily.

Children and Adolescents 12 years and older

5 mg PO once daily.

Children 6 to 11 years

2.5 mg PO once daily.

Oral dosage (oral solution) Adults

5 mg PO once daily.

Children 6 to 11 years

2.5 mg PO once daily.

Children and Adolescents 12 years and older

5 mg PO once daily.

Children 1 to 5 years

1.25 mg PO once daily.

Infants 6 months and older

1 mg PO once daily.

Dosing Considerations
Hepatic Impairment

In adults with hepatic impairment, a starting dose of 5 mg PO every other day is recommended. Recommendations for dosage adjustments in pediatric patients with hepatic impairment are not available, but dosage interval adjustment may be necessary.

Renal Impairment

CrCl 50 mL/minute or less: In adults, 5 mg PO every other day is recommended. Recommendations for dosage adjustments in pediatric patients with renal impairment are not available, but dosage interval adjustment may be necessary.
 
Intermittent hemodialysis
Desloratadine and its metabolite are not removed by hemodialysis. See dosage for CrCl 50 mL/minute or less.

Drug Interactions

Acetaminophen; Aspirin; Diphenhydramine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Caffeine; Pyrilamine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Chlorpheniramine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Chlorpheniramine; Dextromethorphan: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Chlorpheniramine; Phenylephrine : (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Dextromethorphan; Doxylamine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Diphenhydramine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Acetaminophen; Pamabrom; Pyrilamine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Acrivastine; Pseudoephedrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Brompheniramine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Brompheniramine; Dextromethorphan; Phenylephrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Brompheniramine; Phenylephrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Brompheniramine; Pseudoephedrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Brompheniramine; Pseudoephedrine; Dextromethorphan: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Carbinoxamine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Cetirizine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Cetirizine; Pseudoephedrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlophedianol; Dexbrompheniramine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlophedianol; Dexchlorpheniramine; Pseudoephedrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlorcyclizine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Codeine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Dextromethorphan: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Dextromethorphan; Phenylephrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Dihydrocodeine; Phenylephrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Hydrocodone: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Ibuprofen; Pseudoephedrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Phenylephrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Chlorpheniramine; Pseudoephedrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Clemastine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Cyclizine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Cyproheptadine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Dexbrompheniramine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Dexbrompheniramine; Pseudoephedrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Dexchlorpheniramine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Dexchlorpheniramine; Dextromethorphan; Pseudoephedrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Dextromethorphan; Diphenhydramine; Phenylephrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Dimenhydrinate: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Diphenhydramine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Diphenhydramine; Ibuprofen: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Diphenhydramine; Naproxen: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Diphenhydramine; Phenylephrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Doxylamine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Doxylamine; Pyridoxine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Fexofenadine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Fexofenadine; Pseudoephedrine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Heparin: (Minor) Antihistamines may partially counteract the anticoagulant actions of heparin, according to the product labels. However, this interaction is not likely of clinical significance since heparin therapy is adjusted to the partial thromboplastin time (aPTT) and other clinical parameters of the patient.
Hydroxyzine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Levocetirizine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Loratadine: (Major) Desloratadine is the active metabolite of Loratadine. These 2 drugs should not be given at the same time due to the duplication of therapy and the resultant increase in desloratadine concentrations, which may lead to increased CNS or anticholinergic effects.
Loratadine; Pseudoephedrine: (Major) Desloratadine is the active metabolite of Loratadine. These 2 drugs should not be given at the same time due to the duplication of therapy and the resultant increase in desloratadine concentrations, which may lead to increased CNS or anticholinergic effects.
Meclizine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Pseudoephedrine; Triprolidine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Pyrilamine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Sedating H1-blockers: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.
Sincalide: (Moderate) Sincalide-induced gallbladder ejection fraction may be affected by concurrent medications, including H1-blockers. False study results are possible; thorough patient history is important in the interpretation of procedure results.
Triprolidine: (Minor) Although desloratadine is considered a 'non-sedating' antihistamine, dose-related sedation has been noted. For this reason, it would be prudent to monitor for drowsiness during concurrent use of desloratadine with CNS depressants such as other H1-blockers.

How Supplied

Clarinex RediTab/Desloratadine Oral Tab Orally Dis: 2.5mg, 5mg
Clarinex/Desloratadine Oral Tab: 5mg

Maximum Dosage
Adults

5 mg/day PO.

Geriatric

5 mg/day PO.

Adolescents

5 mg/day PO.

Children

12 years: 5 mg/day PO.
6 to 11 years: 2.5 mg/day PO.
1 to 5 years: 1.25 mg/day PO.

Infants

6 to 11 months: 1 mg/day PO.
Less than 6 months: Safety and efficacy have not been established.

Mechanism Of Action

Desloratadine is highly selective for histamine H1-receptors. Unlike cromolyn and nedocromil which block histamine release, H1-antagonists compete with free histamine for binding at H1-receptor sites. This competitive antagonism blocks the effects of histamine on H1-receptors in the GI tract, uterus, large blood vessels, and bronchial smooth muscle. Blockade of H1-receptors also suppresses the formation of edema, flare, and pruritus that result from histaminic activity. At higher concentrations, H1-receptor antagonism becomes relatively irreversible. In vitro studies have demonstrated that desloratadine has a 15-fold higher affinity for the H1-receptor than does the parent compound, loratadine.
 
Desloratadine does not readily cross the blood-brain barrier, and it preferentially binds at H1-receptors in the periphery rather than within the brain, which probably accounts for some of its nonsedating character. H1-blockers are similar in structure to anticholinergics, local anesthetics, antispasmodics, and ganglionic- and adrenergic-blocking agents, sharing some of their properties. H1-blockers possess anticholinergic properties in varying degrees; however, desloratadine does not exert significant anticholinergic effects at therapeutic concentrations.
 
In patients with allergic rhinitis, the inflammatory response plays a prominent role in the development of nasal obstruction and involves a number of mediators. Initial release of histamine from mast cells is followed by late-phase reactions involving a number of other cells, such as fibroblasts, epithelial cells, neutrophils, eosinophils (especially in conditions with raised IgE levels), macrophages, platelets, and lymphocytes. Cell adhesion can also be part of the inflammatory process. Desloratadine has demonstrated anti-inflammatory effects in both in vitro and in vivo studies. The anti-inflammatory action appears to be related to a reduction in eosinophils, neutrophils, interleukin-4 and interleukin-8.

Pharmacokinetics

Desloratadine is administered orally. It is extensively metabolized and only minimal amounts of the orally administered dose are recovered in the urine (less than 2%) and feces (less than 7%). The major metabolic pathway is hydroxylation to form 3-OH-desloratadine that is glucoronidated and the glucuronide conjugate is excreted in the urine and bile. The elimination plasma half-life is approximately 20 to 30 hours. Steady state plasma concentrations are attained in 4 to 6 days.
 
Affected cytochrome P450 (CYP450) isoenzymes and drug transporters: None
Clinically relevant drug interactions related to inhibition of CYP450 system enzymes, such as CYP3A4, or drug transporters (such as P-glycoprotein) with desloratadine have not been noted in drug-drug interaction studies. Desloratadine is a CYP3A4 and P-gp substrate. Increased plasma concentrations (Cmax and AUC) of desloratadine and 3-hydroxydesloratadine were observed with some potent CYP3A4 inhibitors in studies. However, there were no clinically relevant changes in the safety profile of desloratadine, as assessed by electrocardiographic parameters (including the corrected QT interval), clinical laboratory tests, vital signs and adverse events.

Oral Route

Peak plasma concentrations are obtained 3 hours after a 5 mg oral dose of the conventional tablets. Food has no effect on the extent of desloratadine absorption. The conventional tablet, disintegrating tablet, and oral solution are bioequivalent.

Pregnancy And Lactation
Pregnancy

No teratogenic or mutagenic effects were observed in animal studies of desloratadine use during pregnancy in rats or rabbits. Loratadine and cetirizine are often preferred second generation antihistamines based on their excellent safety data and recommendation in multiple guidelines for use during pregnancy. Desloratadine is the major metabolite of loratadine. Results of a large cohort study of desloratadine use in human pregnancy concluded that the safety profile of desloratadine is similar to loratadine and cetirizine.

Desloratadine is distributed into breast milk. According to the manufacturer, the decision should be made to either discontinue breast feeding or discontinue the drug, taking into account the importance of the drug to the mother. However, literature with loratadine, the parent drug, suggests that because of its expected low milk levels and lack of sedation and anticholinergic effects, maternal use of desloratadine is unlikely to affect a breast-fed infant or milk production. In one study, a single loratadine dose of 40 mg was administered to 6 lactating women (note that the suggested daily dose of desloratadine is 5 mg). Average loratadine peak milk concentrations, 2 hours after administration, were 29.2 mcg/L (range 20.4 to 39 mcg/L); average desloratadine peak milk concentrations, 5.3 hours after loratadine administration, were 16 mcg/L (range 9 to 29.6 mcg/L). The total amount excreted in milk over 48 hours was 11.7 mcg of loratadine and desloratadine. However, as noted above, the dose administered was 4 times greater than the usual adult dose of the drug; a total dose of about 3 mcg would be expected with a 10 mg dose. The calculated average and maximum expected doses of loratadine and desloratadine in milk were 0.46% and 1.1% of the maternal weight-adjusted dose, respectively, after the 40 mg dose. Loratadine is considered to be compatible with breast-feeding. The British Society for Allergy and Clinical Immunology recommends loratadine at the lowest dose as a preferred antihistamine in breast-feeding women. 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.