The Treatment with Allelock^® (Olopatadine Hydrochloride) for Patients with Factitious Urticaria

Abstract

Factitious urticaria is a distinct form of chronic urticaria which is easily induced by mechanical stimulation to skin. Although histamine is known to play an important role in the induction of the urticaria, the effect of H1-blockers is not always satisfactory. In this study we tested the efficacy of Allelock^® (Olopatadine hydrochloride) on stimulation-induced whealing in 13 patients with factitious urticaria. The efficacy was evaluated in l2 of 13 patients after an 8 week-trial, and 7 of the 12 patients were treated successfully in the first 4 weeks and 9 of the 12 patients were successfully treated in the next 4 weeks. The blood examination data were all within the normal range in all patients during the trial. These results suggest Allelock^® to therefore be useful for treatment of factitious urticaria.