Bilayer tablet is innovative period for the successful improvement of controlled release formulation along with a variety of features to provide a technique of successful drug delivery system. Controlled release dosage forms have been comprehensively used to improve therapy with several important drugs. Inclusion of drug in controlled release gastro-retentive dosage forms which can remain in the gastric region for several hours would considerably extend the gastric residence time of drugs and improve bioavailability, reduce drug waste and enhance the solubility of drugs that are less soluble in high pH environment. Numerous approaches are presently utilized in the prolongation of Gastric Retention Time, including floating drug delivery system, swelling and expanding systems, polymeric bio adhesive systems, high-density systems, modified shape systems and other deferred gastric emptying strategy
