A placebo-controlled comparative study of sustained-release brompheniramine maleate against clemastine fumarate in the treatment of chronic urticaria.

A partially-blind, three-way crossover study was carried out in 24 patients suffering from chronic urticaria to compare the efficacy and tolerance of brompheniramine maleate with that of clemastine fumarate. Patients received 4-week courses of treatment with 1 tablet twice daily of either 12 mg brompheniramine, 1 mg clemastine or placebo, in random order. Assessments were made by the physician of the patients' condition on entry and of response to treatment at the end of each 2-week period throughout the 12-week study period. At the end of the trial, patients were asked to state their preference, if any, for the different treatments. The results showed that both antihistamines were significantly effective compared to placebo and that at the dosage used brompheniramine was considered significantly better than clemastine in long-term control. Drowsiness was experienced by 4 patients whilst taking brompheniramine compared to 3 patients whilst taking clemastine. One patient experienced anorexia and vomiting with brompheniramine and 4 patients developed gastro-intestinal upsets whilst taking the placebo.