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Abstract Gastroretentive dosage forms are especially designed dosage forms that are retained in the stomach. They can help in reaching sustained drug delivery mainly for drugs that show site specific absorption from the upper intestine or from the stomach. This encompasses drugs which have local action in the stomach such as antacids and drugs acting locally on ulcers. Also, drugs which have narrow absorption window from the upper intestine tract such as actively transported drugs. Many pharmacodynamic advantages can be achieved through the preparation of gastroretentive dosage forms. These include reduced fluctuation in drug effects and improved selectivity in receptor activation. Gastroretentive dosage forms can be classified into high density (sinking), low density (floating), expandable, super porous hydrogels, mucoadhesive and magnetic systems. Low density floating systems are further subdivided into effervescent and non-effervescent systems. Effervescent systems encompass raft forming and gas forming systems. Non effervescent systems encompass hydrodynamically balanced systems, Microspheres, oil loaded multiparticulate systems and the use of low density foam powder. Irritable bowel syndrome (IBS) is a disorder characterized most commonly by cramping, abdominal pain, bloating, constipation, and diarrhea. IBS causes a great deal of discomfort and distress, but it does not permanently harm the intestines and does not lead to a serious disease, such as cancer. Most people can control their symptoms with diet, stress management, and prescribed medications |