Pulsatile Drug Delivery Systems are gaining a lot of interest as they deliver the drug at the right place at the right time and in the right amount, thus providing spatial and temporal delivery and increasing patient compliance. Pulsatile Drug Delivery systems (PDDS) are basically time-controlled drug delivery systems in which the system controls the lag time independent of environmental factors like pH, enzymes, gastro-intestinal motility, etc. These systems are designed according to the circadian rhythm of the body. The principle rationale for the use of pulsatile release of the drugs is where a constant drug release is not desired. A pulse has to be designed in such a way that a complete and rapid drug release is achieved after the lag time. Various systems like capsular systems, osmotic systems, single and multiple-unit systems based on the use of soluble or erodible polymer coating and use of rupturable membranes have been dealt with in the article. These systems are beneficial for the drugs having chronopharmacological behavior where night time dosing is required, such as anti-arhythmic and anti-asthmatic. Some of the disease conditions wherein PDDS are promising include duodenal ulcer, cardiovascular diseases, arthritis, asthma, diabetes, neurological disorder, cancer, hypertension and hypercholesterolemia. PDDS can be classified into time controlled systems wherein the drug release is controlled primarily by the delivery system, stimuli induced PDDS in which release is controlled by the stimuli, such as the pH or enzymes present in the intestinal tract or enzymes present in the drug delivery system and externally regulated system where release is programmed by external stimuli like magnetism, ultrasound, electrical effect and irradiation. Current review article discussed the reasons for development of pulsatile drug delivery system, types of the disease in which pulsatile release is required, classification, advantages, limitation, and Polymers used in pulsatile drug delivery system. To introduce the concept of chronotherapeutics, it is important to define the following concepts

Abstract1-Monocaproin, a 1-monoacylglycerol, was synthesized with the reaction of glycidol by chromium-caproic fatty acid complexes and was found to be amphiphilic in nature. Synthesized 1-monocaproin was characterized by thin-layer chromatography, and the residual chromium was analyzed using inductively coupled plasma mass spectroscopy. Vascular endothelium growth factor (VEGF)-mediated angiogenesis pathways are being targeted for the development of novel drugs suitable for inhibition or stimulation of angiogenesis in various pathologies. In the chicken egg Chorioallantoic membrane (CAM) assay, 1-monocaproin exhibited VEGF-induced neovascularization in a dose-dependent manner. Synthesized 1-monocaproin was found to show the angiogenic effect at a dose concentration equivalent to VEGF at 1,000 ppm. The results thus suggest that 1-monocaproin should be considered as a useful drug candidature targeting angiogenesis in coronary artery disease, stroke, and postsurgical therapy.