Formulation and In Vitro Evaluation of Buccal Tablet of Famotidine

Famotidine is histamine –H2 receptor antagonist. It has bioavailability of 40 to 45% and it has shorter plasma half life of 2.5 to 3.5 hrs. The effective treatment of erosive esophagitis and Zolinger-Elisons syndrome requires administration of 20 mg of Famotidine 4 times a day. A conventional dose of 20 mg can inhibit gastric acid secretion up to 5 hours but not up to 10 hours. An alternative dose of 40 mg leads to plasma fluctuations; thus a sustained release dosage form of famotidine is desirable. Direct access to the systemic circulation bypasses drugs from the hepatic first pass metabolism leading to high bioavailability. Moreover, the buccal route is easily accessible, has a good patient compliance and can be used in patients who can’t swallow. Bilayer buccal tablet was prepared by using mucoadhesive polymer combination of Sodium CMC and Carbopol934P, by direct compression with backing layer of Ethyl cellulose. The optimized formulation F1 had given release of 102.57% in 8hrs and it had optimum swelling, mucoadhesive property and permeation from buccal mucosa. It also had desired drug release kinetics and found to be stable for the period of 1 month.