Alcaftadine: a topical antihistamine for use in allergic conjunctivitis.

Alcaftadine (Lastacaft®; Allergen, Inc.) is a broad-spectrum antihistamine displaying a high affinity for histamine H1 and H2 receptors and a lower affinity for H4 receptors. It also exhibits modulatory action on immune cell recruitment and mast cell stabilizing effects. The authors reviewed all available English-language literature characterizing the efficacy, safety and pharmacokinetic profile of alcaftadine ophthalmic solution. In the studies reviewed, alcaftadine was more effective than placebo and at least as effective as olopatadine 0.01% in preventing ocular itching at 15 minutes and at 16 hours after administration. Alcaftadine 0.025% ophthalmic solution has been approved by the U.S. Food and Drug Administration for prevention of itching associated with allergic conjunctivitis in patients over 2 years of age. Comparative efficacy data of alcaftadine to other ocular antihistamine/mast cell stabilizers are limited.