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...