Adults

The usual recommended dose of Levocetirizine for adults is 5 mg once daily. For Seebrox 15 mg syrup, a doctor's guidance is essential to determine the appropriate volume corresponding to a 5 mg or other suitable therapeutic dose, as 15 mg is typically higher than a standard single adult dose.

Elderly

No dosage adjustment is generally required in elderly patients with normal renal function. For those with impaired renal function, dosage should be adjusted based on creatinine clearance.

Renal_impairment

Dosage should be adjusted based on creatinine clearance. For patients with mild renal impairment (CrCl 50-79 mL/min), 5 mg once daily. For moderate impairment (CrCl 30-49 mL/min), 5 mg every other day. For severe impairment (CrCl <30 mL/min), 5 mg twice weekly. Not recommended for end-stage renal disease patients.

Onset

Onset of action typically occurs within 1 hour.

Excretion

Primarily excreted unchanged in the urine (approximately 85.4% of the dose) and to a lesser extent in feces (12.9%).

Half life

Plasma elimination half-life is approximately 7 to 10 hours.

Absorption

Rapidly absorbed after oral administration, reaching peak plasma concentrations in about 0.9 to 1 hour.

Metabolism

Less than 14% of the dose is metabolized in humans by O-dealkylation, with negligible cytochrome P450 involvement.

Ritonavir

May increase the plasma levels of levocetirizine, although not clinically significant.

Central Nervous System Depressants

Concurrent use with alcohol or other CNS depressants (e.g., sedatives, hypnotics, tranquilizers) may cause additional reductions in alertness and impair CNS performance.