2010 Volume 41 Issue 6 Pages 309-315
Levocetirizine hydrochloride is the R-enantiomer of the racemic compound cetirizine hydrochloride, and has been found to be a novel antihistaminic agent for the treatment of allergic rhinitis, urticaria, eczema, dermatitis, prurigo and dermal pruritus.
The objective of the present study was to investigate the pharmacokinetics of levocetirizine, when administered as the R-enantiomer (levocetirizine hydrochloride 5 mg and 10 mg) or as the racemic compound (cetirizine hydrochloride 10 mg) in healthy Japanese male volunteers.
The plasma concentration profiles of levocetirizine were similar following administration of cetirizine hydrochloride at a dose of 10 mg and levocetirizine hydrochloride at a dose of 5 mg in twenty Japanese healthy male subjects. Equivalent exposure of levocetirizine was obtained by administering levocetirizine hydrochloride at half the dose of cetirizine hydrochloride.
When single oral doses of 5 mg and 10 mg of levocetirizine hydrochloride were administered to 20 healthy Japanese adult male subjects under fasting conditions, the absorption of levocetirizine from the gastrointestinal tract was fast. The tmax values were 0.75-1 hour and the terminal phase half-lives were 7.3-7.6 hours, and did not change depending on the dose level. The exposure of levocetirizine increased with dose.
No adverse events were reported following administration of single oral doses of 5 mg and 10 mg of levocetirizine hydrochloride and 10 mg of cetirizine hydrochloride under fasting conditions, confirming the safety and tolerability of levocetirizine.
