A comparison of acrivastine versus hydroxyzine and placebo in the treatment of chronic idiopathic urticaria.

A total of 21 patients with a diagnosis of chronic idiopathic urticaria were assessed in a fully randomized, double-blind, crossover study to investigate the efficacy of 8 mg acrivastine versus 20 mg hydroxyzine and placebo administered three times daily. Both acrivastine and hydroxyzine were found to be effective, and significantly better than placebo, in controlling signs and symptoms of urticaria. No significant differences were found between the active preparations. Hydroxyzine was associated with significantly more reports of drowsiness than was placebo.