Ketotifen is a synthetic chemical compound primarily used as an antihistamine and mast cell stabilizer in pharmaceutical applications. It serves as the active pharmaceutical ingredient (API) for managing various allergic conditions, including allergic conjunctivitis (preventing and treating redness, itching, and watering of the eyes), allergic rhinitis, allergic asthma (reducing frequency and severity of attacks by inhibiting the release of inflammatory mediators from mast cells), chronic urticaria (hives), and other allergic skin conditions (providing relief from itching and swelling). Its dual mechanism of action—blocking H1 histamine receptors and stabilizing mast cells—makes it effective for long-term allergy management and prophylactic treatment to minimize reactions in individuals with known sensitivities. This high-purity product is supplied as a solid for research, development, and pharmaceutical manufacturing purposes.