Effectiveness of Levocabastine Eyedrops in Children with Allergic Conjunctivitis: A Double-Blind Study

A randomized, crossover double-blind, placebo-controlled study was conducted to evaluate the effectiveness of levocabastine (LEV) eyedrops on top of oral terfenadine in 23 children with allergic conjunctivitis due to Dermatophagoides pteronyssinus (DPT). After determination of the baseline allergic reaction threshold, a conjunctival provocation test with a DPT extract at increasing concentration was performed after an oral dose of terfenadine (T) and the instillation of either LEV or placebo (P) eyedrops in each eye. In 74% of the children treated with LEV on top of T, the threshold allergen concentration shifted from 10,000 to 100,000 SQ-U/ml, the highest dose used, versus 57% of the children treated with T and P (p<0.001). Moreover, 43% of the children under T and LEV did not experience ocular symptoms with the top dose versus 26% of children treated with T and P (p<0.001). The results of this study indicate that LEV eyedrops added to oral T increase the conjunctival threshold dose of the specific allergen in children with allergic conjunctivitis to DPT. These data indicate an additive effect of a topical antihistamine (LEV) on top of oral antihistamine (T) treatment.