Floating drug delivery system or hydrodynamically balance systems have a bulk density lower than gastric fluid and thus remains buoyant in the stomach for a prolonged period of time without affecting the gastric emptying rate. While the system is floating on gastric contents the drug is released slowly at a desired rate from the system. After the release of drug residual system is emptied from the stomach. This results in increase in gastric residence time and a better control of fluctuation in plasma drug concentration. Development of oral controlled-release systems has been a challenge to...