Background: We investigated the early efficacy of topical levocabastine, an H(1) histamine-receptor antagonist, in improving the clinical symptoms of allergic conjunctivitis.
Methods: Thirty-six patients with allergic conjunctivitis were enrolled. One drop of levocabastine was instilled in one eye and one drop of artificial tears in the contralateral eye. Clinical examinations were performed before, and 15 and 30 minutes after instillation. Symptoms of itching and signs of injection were assessed at each time point.
Results: Both levocabastine and artificial tears resulted in a statistically significant reduction in ocular itching. However, levocabastine was significantly more effective.
Conclusions: Although artificial tears had a positive effect in reducing symptoms of allergic conjunctivitis, by the washing out of allergens, levocabastine was more effective than artificial tears in controlling acute symptoms of allergic conjunctivitis, demonstrating that the selective H1 histamine-receptor antagonist action of levocabastine is rapidly effective in a clinical setting.