Ebastine is a new
piperidine-containing, relatively nonsedating second-generation H1-receptor antagonist. In a double-blind, parallel-group study of a single 5 mg or 10 mg dose of
ebastine syrup used to treat
allergic rhinitis in 20 children aged 6 to 12 years, we tested the hypothesis that the medication would have a duration of action of at least 24 hours. We measured plasma concentrations of
carebastine, the pharmacologically active metabolite of
ebastine, and the wheals and flares produced by epicutaneous tests with
histamine phosphate, 1.0 mg/ml.
Ebastine was absorbed well; peak
carebastine concentrations occurred approximately 3 hours after dosing. Mean plasma elimination half-life values of
carebastine ranged from 10 to 14 hours. The pharmacokinetics of
carebastine were linear and dose independent in the dosage range studied. After the 5 or 10 mg dose, there were no significant differences between mean plasma elimination half-life values, mean oral clearance values, or mean apparent volumes of distribution. Mean peak plasma
carebastine concentrations and mean areas under the plasma
carebastine concentration-time curve after the 10 mg dose were 1.93 and 1.76 times, respectively, the values obtained after the 5 mg dose. Both doses significantly reduced the
histamine-induced wheal-and-flare areas for up to 28 hours compared with predose values. The differences in effect between the doses generally were not statistically or clinically significant. No adverse effects were noted. We conclude that
ebastine, an effective H1-receptor antagonist with a prompt onset of action and a long duration of action, is suitable for once-daily administration to children.