Relative Efficacy of Seven Common H1 Receptor Antagonist Antihistamines in Chronic Idiopathic Urticaria.

The order of clinical potency of seven Hi receptor antagonist antihistamines in usual therapeutic doses was evaluated in 30 patients of chronic idiopathic urticaria by a double blind, placebo controlled trial utilizing a self-assessment method. The analysis of mean whealing and, itching scores established a potency sequence in the -decreasing order of cyproheptidine, hydroxyzine, chlorpheniramine, embramine, promethazine, dimeth'mdene and dexchlorpheniramme. The differences between the first five antihistamines were not statistically significant, though these were superior to ddxchlorpheniralmine and placebo. Dexchlorpheniramine was statistically better than placebo.