Pharmacology, clinical efficacy and safety of olopatadine hydrochloride

Olopatadine is a multimechanism anti-allergic agent that inhibits H(1) receptor activation and stabilizes mast cell membranes, blocking the release of allergic and inflammatory mediators. Studies in human conjunctival mast cells clearly demonstrate, in the relevant tissue and species, olopatadine's inhibition of histamine release, which was subsequently confirmed in allergen-challenged subjects. Its comfort and tolerability may be related to the absence of perturbation of cell membranes, in contrast to many anti-allergics, whose disruption of membranes lead to histamine release even at therapeutically relevant concentrations. In preclinical and clinical studies, olopatadine had greater efficacy and comfort than other anti-allergic agents available today for ophthalmic use.