Biological Activity: Azelastine hydrochloride (Astelin) is a potent, second-generation, selective, histamine antagonist. [1] Azelastine hydrochloride (Astelin) has a triple mode of action: Anti-histamine effect, mast-cell stabilizing effect and anti-inflammatory effect. Azelastine hydrochloride (Astelin) has a rapid onset of action: 15 minutes with the nasal spray and 3 minutes with the eye drops. The effect lasts for 12 hours. [2][3][4] |