The present invention discloses oral, gastro retentive pharmaceutical composition for . sustained and continuous drug release comprising Lafutidine its derivatives or pharmaceutically acceptable salts as active agent in the range of 5-40% of the total composition, hydroswelling polymer or mucoadhesive polymer in the range of 25-90% optionally with completing agent selected from monovalent or divalent ions such as calcium carbonate along with pharmaceutically acceptable excipients.