CLARITIN HIVES RELIEF
Clinical safety rating: caution
Comprehensive clinical and safety monograph for CLARITIN HIVES RELIEF (CLARITIN HIVES RELIEF).
Selective inverse agonist at histamine H1 receptors, blocking histamine-mediated effects in allergic reactions.
| Metabolism | Primarily hepatic via CYP3A4 and CYP2D6; forms active metabolite desloratadine. |
| Excretion | Renal: ~40% as metabolites, <1% unchanged; Fecal: ~40%; Biliary: minor contribution. |
| Half-life | 8.4 hours (range 3-20 hours) for loratadine; 28 hours (range 8.8-92 hours) for active metabolite desloratadine, allowing once-daily dosing. |
| Protein binding | Loratadine: 97-99% to albumin and alpha-1-acid glycoprotein; desloratadine: 73-76%. |
| Volume of Distribution | Loratadine: 120 L/kg, indicating extensive tissue distribution; desloratadine: 40 L/kg. |
| Bioavailability | Oral: ~100% (loratadine is rapidly and well absorbed; first-pass metabolism to desloratadine reduces parent drug concentration but active metabolite contributes to effect). |
| Onset of Action | Oral: 1-3 hours after ingestion. |
| Duration of Action | 24 hours, supporting once-daily dosing for allergic rhinitis and urticaria. |
10 mg orally once daily
| Dosage form | TABLET |
| Renal impairment | GFR 30-89 mL/min: no adjustment; GFR <30 mL/min: 5 mg orally once daily |
| Liver impairment | Child-Pugh A: no adjustment; Child-Pugh B or C: 5 mg orally once daily |
| Pediatric use | 6-11 years: 5 mg orally once daily; 12 years and older: 10 mg orally once daily |
| Geriatric use | No specific adjustment; use caution due to age-related renal impairment may require 5 mg once daily |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for CLARITIN HIVES RELIEF (CLARITIN HIVES RELIEF).
| Breastfeeding | Loratadine is excreted into breast milk; M/P ratio is approximately 1.17 for parent drug and 0.85 for active metabolite. Concentrations are low, and adverse effects in nursing infants are unlikely. Considered compatible with breastfeeding, but monitor infant for sedation or irritability. |
| Teratogenic Risk | Loratadine is categorized as FDA Pregnancy Category B. Animal studies have not demonstrated fetal harm, but adequate, well-controlled studies in pregnant women are lacking. No known teratogenic risk in any trimester; however, first-trimester exposure should be with caution. |
■ FDA Black Box Warning
None.
| Serious Effects |
Hypersensitivity to loratadine or any component; severe hepatic impairment; pediatric patients <6 years of age (for this product).
| Precautions | Caution in patients with hepatic or renal impairment; avoid use with alcohol or CNS depressants; may cause drowsiness or dizziness; use with caution in elderly patients. |
Loading safety data…
| Fetal Monitoring | No specific fetal monitoring required. Standard prenatal care with assessment of fetal growth and development is sufficient. Monitor maternal blood pressure and heart rate if high doses used. |
| Fertility Effects | No known adverse effects on fertility in animal studies. No human data suggest impairment of male or female reproductive function. |