Azelastine: a multifaceted drug for asthma therapy.

Azelastine (4-(p-chlorobenzyl)-2-(hexahydro-1-methyl-1H-azepin-4-yl)-1-(2H)-p hthalazinone hydrochloride), a novel long-acting antiasthmatic/antiallergic drug has been demonstrated to be effective in the treatment both of asthma and of allergic rhinitis. In this paper some selected properties of azelastine are presented which might contribute to its antiasthmatic and antiallergic effect. Azelastine causes a marked inhibition of generation of oxygen radicals in alveolar macrophages. A bronchosecretolytic activity of azelastine is observed which is based on the secretion of a more liquid mucus. Furthermore, the mucociliary clearance is enhanced as demonstrated in a rabbit model. Also IL-1 generation is inhibited in vitro and in vivo. Finally, the possible tissue and cellular accumulation of azelastine in lung and alveolar macrophages resp. is discussed.