methapyrilene

Methapyrilene is a first-generation ethylenediamine H1-antihistamine and anticholinergic of the pyridine chemical class developed in the early 1950s. It was primarily used for its sedative effects to treat insomnia and as an anti-allergic agent. Methapyrilene acts as a histamine H1 receptor antagonist by interfering with the agonist action of histamine at the H1 receptor, thereby attenuating inflammatory processes such as allergic rhinitis and urticaria. It also exhibits anticholinergic properties. The drug readily crosses the blood-brain barrier and causes significant sedation. Methapyrilene was withdrawn from markets worldwide in 1979 after it was shown to be a potent carcinogen causing liver cancer in animal studies[1][3][4][6].

Brand names

Co-PyronilHistadyl ECSominexNytolSleep-EzeExcedrin PM

Other names

methapyrilene hydrochloridemethapyrilene fumarate