... stabilizer. It is most commonly sold in as a salt of fumaric Acid, ketotifen fumarate, and is available in two forms ... Lomb), Zyrtec Itchy-Eye Drops, and Claritin Eye. A generic version of Novartis' Zaditor, ketotifen fumarate ophthalmic solution, 0.025%, is available ... .345mg/ml, 0.25mg as ketotifen)' which is a generic version of Zaditor and is selling as Over-The-Counter is also ...