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 micrograms histamine-induced weal and flare areas. Compared with placebo, both doses of dimethindene and chlorpheniramine significantly (P less than 0.001) reduced weal area. Both doses of dimethindene (P less than 0.001) and chlorpheniramine (P less than 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 less than 0.01) compared with chlorpheniramine and reduced flare area significantly (P less than 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.