Prazosin is used alone or in combination with other medications to treat high blood pressure. Prazosin is in a class of medications called alpha-blockers. It works by relaxing the blood vessels so that blood can flow more easily through the body. Floating drug delivery systems are most commonly used technique for achieving gastric retention. This delivery system is desirable for drugs with an absorption window in stomach or in the upper small intestine. These have a bulk density less than gastric fluids and so remain buoyant in the stomach without affecting gastric emptying rate for a prolonged period of time. Drugs having less half-life, when incorporated into floating delivery system may exhibits better release and improve bioavailability of the drug by maintaining good level of plasma drug concentration and thereby minimizes repeated drug administration and fluctuation and plasma concentration. Prazosin HCL is Freely Soluble in water and good protein binding so small quantity can be used in postural hypotension. It will enhance the penetration and provide prolonged release. Hope this book will be helpful to the researchers in the field of Pharmaceutics and Biomedical Sciences.