Azatadine dimaleate

Azatadine is an histamine and cholinergic inhibitor with IC50 of 6.5 nM and 10 nM, respectively. Azatadine puts back the onset of dyspnea-induced by aerosolized histamine, acetylcholine and serotonin in the conscious guinea-pig with PD50 of 0.01 mg/kg, 0.739 mg/kg and 0.86 mg/kg. It protects conscious guinea-pigs against death induced by the intravenous injection of histamine with oral PD50 of 0.009 mg/kg in guinea-pig and 0.22 mg/kg in mice. Azatadine (1 mg twice daily for 14 days) is effective in relieving the histamine-mediated symptoms of seasonal allergic rhinitis.