Comparative Effect of Dimethindene Maleate and Chlorpheniramine Maleate on Histamine-Induced Weal and Flare

Abstract

Antihistaminic activity of 3 or 6 mg dimethindene maleate was compared with that of placebo and 12 mg chlorpheniramine maleate in 60 healthy volunteers in a randomized, crossover study. Activity of each drug was assessed by measuring 2 μg histamine-induced weal and flare areas. Compared with placebo, both doses of dimethindene and chlorpheniramine significantly ( P < 0.001) reduced weal area. Both doses of dimethindene ( P < 0.001) and chlorpheniramine ( P < 0.05) also significantly reduced flare area. Dimethindene (6 mg) brought about the maximum reduction in weal area (28.8%) and flare area (39.1%). Dimethindene (6 mg) also reduced weal area significantly ( P < 0.01) compared with chlorpheniramine and reduced flare area significantly ( P < 0.05) compared with 3 mg dimethindene. Using a 100 mm visual analogue scale for assessment of weal and flare intensities, 6 mg dimethindene again produced the maximum response. The study confirmed that the antihistamine activity of dimethindene was better than that of chlorpheniramine.