first pass metabolism.

In the recent years the pulsatile drug release systems are gaining growing interest. The pulsatile drug release where the drug is rapidly released after the well defined lag-time could be advantageous for many drugs or therapies. The sustained & controlled release devices are not applicable in some of the cases like the time-programmed administration of the hormones & many drugs. The living systems are the predictable dynamic resonating systems which require different amounts of drug at the expected times within the circadian cycle. The pulsatile drug delivery system has fulfilled this requirement. This system is such a system where the drug is released suddenly after the well-defined lag time or the time gap according to the circadian rhythm of the disease states. No drug is released from the device within this lag time. This method is good for the drugs with the extensive first pass metabolism & targeted to the specific site in the intestinal tract. The current article focuses on the necessities of pdds, diseases requiring PDDS, classification of pulsatile drug delivery system, current situation and future scope& marketed technologies of pulsatile drug delivery system.