DIMETINDENE VERSUS ASTEMIZOLE IN THE TREATMENT OF ITCHING ECZEMATOUS DISORDERS - A RANDOMIZED, DOUBLE-BLIND, COMPARATIVE TRIAL

We performed a randomized, double-blind double-dummy trial to compare the antipruritic efficacy and tolerability of dimetindene 2.5 mg (DIM) versus astemizole 10 mg (AST) over a 2-week treatment. Forty-five patients suffering from eczematous disorders or lichen planus were initially included. Out of them, 42 were finally evaluable. Patients recorded pruritus intensity twice-daily on a visual analogue scale (VAS). In the analysis on the VAS data both products revealed to be effective on pruritus. DIM appeared to exhibit a faster onset of action and higher efficacy than AST, but the difference failed to show statistical significance. The reduction In the number of scratch marks was larger with DIM than with AST (p = 0.003 and p = 0,03, after 1 and 2 weeks of treatment, respectively). In the investigators' and the patients' ratings, a significant difference was found after one week in favour of DIM (p < 0,01, for both ratings), which continued as a trend after two weeks (p = 0,061 and p = 0,078 respectively). Overall tolerability was good for both products. The most commonly reported unwanted event on both drugs was drowsiness, but it did not interfere with daily activities. Drowsiness tended to be shorter and milder on AST than on DIM, but other CNS effects such as dizziness and tiredness, occurred with AST. In conclusion, dimetindene was shown to reduce itching faster and more effectively thatn astemizole, confirming thus its valuable contribution to the treatment of pruriginous skin disorders.