XYZAL
Clinical safety rating: caution
Comprehensive clinical and safety monograph for XYZAL (XYZAL).
Levocetirizine is a selective histamine H1-receptor antagonist; it inhibits the histamine-mediated responses in allergic conditions.
| Metabolism | Approximately 86% excreted unchanged in urine; minor hepatic metabolism (oxidative O-dealkylation) via CYP3A4. |
| Excretion | Approximately 84% of a dose is excreted renally as unchanged drug; 12% in feces via biliary elimination. |
| Half-life | Terminal elimination half-life is approximately 7 hours in healthy adults; prolonged to 8–11 hours in elderly and in renal impairment. |
| Protein binding | Approximately 95–96% bound primarily to human serum albumin. |
| Volume of Distribution | 0.3–0.4 L/kg, indicating distribution primarily in extracellular fluid. |
| Bioavailability | Oral bioavailability is approximately 80–90%. |
| Onset of Action | Oral: 1 hour (antihistamine effect); intranasal: 15 minutes. |
| Duration of Action | Approximately 24 hours; clinical effect may persist longer due to high receptor affinity. |
| Molecular Weight | 388.9 |
| Action Class | H1 Antihistaminics (second Generation) |
| Brand Substitutes | Lecope Tablet, LCZ Tablet, 1-AL Tablet, Hatric Tablet, Levocet Tablet, Vocetin 2.5mg Syrup, Grilcet 2.5mg Syrup, Zucet Syrup, 1-AL Syrup, Belrin-LZ Syrup, Levosiz 10 Tablet, LCZ 10 Tablet, Imusun 10mg Tablet, 1-AL 10 Tablet, Valicet 10mg Tablet |
5 mg orally once daily in the evening.
| Dosage form | TABLET |
| Renal impairment | CrCl 30-50 mL/min: 5 mg every other day; CrCl <30 mL/min or ESRD: contraindicated. |
| Liver impairment | No adjustment required for mild to moderate impairment; severe impairment not studied. |
| Pediatric use | 6-11 years: 2.5 mg orally once daily in the evening; ≥12 years: 5 mg orally once daily. |
| Geriatric use | No specific adjustment; use with caution due to potential increased sensitivity and renal impairment. |
| 1st trimester | Limited data; no increased risk of major malformations in human studies. Use only if clearly needed. |
| 2nd trimester | No known fetal harm; consider risk-benefit. |
| 3rd trimester | No known fetal harm; consider risk-benefit. |
Clinical note
Comprehensive clinical and safety monograph for XYZAL (XYZAL).
| Placental transfer | Levocetirizine crosses the placenta; extent unknown but likely low due to molecular properties. |
| Breastfeeding | Levocetirizine is excreted into breast milk in small amounts. Monitor infant for drowsiness or irritability. Compatible with breastfeeding. |
| Lactation Rating |
■ FDA Black Box Warning
None.
| Serious Effects |
Hypersensitivity to levocetirizine or any ingredientSevere renal impairment (CrCl < 10 mL/min)End-stage renal disease
| Precautions | Use with caution in patients with renal impairment (dose adjustment required based on creatinine clearance), May cause somnolence; avoid activities requiring mental alertness, Caution in elderly patients due to potential increased sensitivity, Avoid concurrent use with alcohol or other CNS depressants |
| Food/Dietary | No specific food interactions reported. Food does not significantly affect absorption; however, taking with meals may reduce mild gastrointestinal upset. Avoid alcohol concurrently to prevent additive CNS depression. |
Loading safety data…
| L2 (Safer) |
| Teratogenic Risk | FDA Pregnancy Category B. Animal studies show no fetal harm; no adequate human studies in first trimester. Risk cannot be ruled out; use only if clearly needed. |
| Fetal Monitoring | Monitor for maternal sedation and dizziness; fetal heart rate monitoring if used near term. |
| Fertility Effects | No known adverse effects on fertility in animal studies; human data lacking. |
| Clinical Pearls |
| Levocetirizine (XYZAL) is the active R-enantiomer of cetirizine, offering twice the potency at half the dose. Its primary advantage is lower CNS penetration, reducing sedation compared to first-generation antihistamines; however, somnolence can still occur, especially at higher doses. Onset of action is within 1 hour, with duration of 24 hours, allowing once-daily dosing. It is effective for both seasonal and perennial allergic rhinitis and chronic urticaria. Renal impairment requires dose adjustment: CrCl 50-79 mL/min: 2.5 mg once daily; CrCl 30-49 mL/min: 2.5 mg every other day; CrCl <30 mL/min or ESRD: contraindicated. |
| Patient Advice | Take exactly as prescribed, usually once daily in the evening to minimize daytime drowsiness. · Avoid driving or operating heavy machinery until you know how this medication affects you, as it may cause drowsiness. · Do not exceed the recommended dose; higher doses increase the risk of sedation. · If you have kidney disease, inform your doctor; dose adjustments are necessary. · Use caution with alcohol or other CNS depressants; they can worsen drowsiness. · Store at room temperature away from moisture and heat. |