The molecule is an organoammonium salt consisting of equimolar amounts of ketotifen(1+) and fumarate(1-) ions. A blocker of histamine H1 receptors with a stabilising action on mast cells, it is a non-bronchodilator anti-asthmatic drug. It has a role as an anti-asthmatic drug and a H1-receptor antagonist. It contains a fumarate(1-) and a ketotifen(1+).
(E)-4-hydroxy-4-oxobut-2-enoate;2-(1-methylpiperidin-1-ium-4-ylidene)-6-thiatricyclo[8.4.0.03,7]tetradeca-1(14),3(7),4,10,12-pentaen-8-one