Azelastine nasal spray: a review of pharmacology and clinical efficacy in allergic and nonallergic rhinitis.

Azelastine hydrochloride is a pharmacologically distinct H1-receptor antagonist with a broad spectrum of antiallergic and anti-inflammatory activity. Azelastine has established antiallergic and anti-inflammatory effects that are unrelated to H1-receptor antagonism, including inhibitory effects on the synthesis of leukotrienes, kinins, and cytokines; the generation of superoxide free radicals; and the expression of the intercellular adhesion molecule 1. Azelastine is available in the United States as a nasal spray formulation (Astelin) and is approved for treatment of seasonal allergic rhinitis and nonallergic vasomotor rhinitis. In U.S. clinical trials, azelastine nasal spray was effective in treating all of the symptoms of the allergic rhinitis symptom complex including ocular symptoms, and in double-blind clinical trials in nonallergic vasomotor rhinitis, azelastine nasal spray was effective in treating the total vasomotor rhinitis symptom complex including individual symptoms of nasal congestion and postnasal drip. This article reviews the pharmacologic profile and clinical efficacy and safety of azelastine nasal spray.