Efficacy and safety of astemizole, a long-acting and nonsedating H1 antagonist for the treatment of chronic idiopathic urticaria.

The efficacy and safety of astemizole (AST), a new long-acting H1 antagonist with minimal sedative or anticholinergic side effects, were studied in an 8-week double-blind trial of 51 patients with chronic idiopathic urticaria. Patients with chronic idiopathic urticaria were randomized to AST-treated (10 mg every day) or placebo-treated groups. Patients were followed at weekly intervals and evaluated for pruritus, erythema, extent of wheals, frequency of urticarial episodes, and total control of urticaria. Only three of 27 AST-treated patients stopped the double-blind phase before 8 weeks because of inadequate response as compared to 11 of 24 placebo-treated subjects (p = 0.027). On the last evaluable visit of the double-blind phase of the study, 85% of the AST-treated patients reported an excellent or good response compared to 30% of the placebo-treated group (p = 0.0001). AST-treated patients also reported significant improvement compared to placebo-treated patients in pruritus (p = 0.0001), erythema (p = 0.0001), and extent of wheals (p = 0.003). Mild sedative effects were observed in only two of 27 patients receiving AST. It was concluded that AST is a potent and safe drug for symptomatic control of chronic idiopathic urticaria.