Ketotifen Fumarate (Zaditen)

SYNTHESIS AND DRUG PROFILE

H₁-antagonists with classical structure

Newer agents

Ketotifen Fumarate (Zaditen)

Synthesis

Properties and uses: Ketotifen fumarate is a white to brownish-yellow crystalline powder, sparingly soluble in water, slightly soluble in methanol and in acetonitrile. The recommended dose of ketotifen solution is one drop instilled into each affected eye every 8–12 hr. Most frequently used for conjuctival infection, and rhinitis. Ketotifen solution should be used with caution during pregnancy or during nursing. This is an analogue of the tricyclic H₁-receptor antagonist and serotonin receptor antagonist. It has only minor anticholinergic and antiserotonergic activity. It has been used in the prophylactic treatment of asthma.

Assay: Dissolve the sample in a mixture of anhydrous acetic acid and acetic anhydride and titrate against 0.1 M perchloric acid. Determine the end point potentiometrically.

Dose: Usually, the dose is 1 mg orally two times a day.