Floating drug delivery systems are utilized to target drug release in the stomach or to the upper parts of intestine. Oral delivery of an anti-ulcer agent, famotidine was facilitated by preparing various floating dosage forms which can increase its absorption in the stomach by enhancing gastric residence time. Polymers utilized were hydroxypropyl methylcellulose K15M (HPMC K15M) and hydroxypropyl methylcellulose K100M (HPMC K100M) as gel forming agents along with sodium bicarbonate and citric acid as gas generating agents. Formulated tablets were evaluated for their physicochemical properties as well as drug release profile. Effect of effervescent agents and polymeric substances were also investigated for floating properties and drug release characteristics. Drug release pattern of all formulations followed non-fickian diffusion or anomalous diffusion.