Technological Aspects, Challenges and Applications of Pulsatile Drug Delivery System-A Critical Review

The medicine is constantly released via a sustained and regulated drug delivery system per unit. However, there are several situations where it is undesirable to keep a drug's blood level constant. In these circumstances, pulsatile drug delivery could be preferable. Pulsatile drug delivery systems (PDDS) are gaining popularity because they deliver the medicine to the correct site of action at the proper time and in the right amount, offering spatial and temporal delivery and boosting patient compliance. These are essentially time-controlled drug delivery systems in which the system manages the lag time independent of environmental parameters such as pH, enzymes, gastrointestinal motility, etc. PDDS can be divided into three categories: time-controlled systems, where the delivery system controls drug release primarily; stimuli-induced systems, where release is programmed by external stimuli like magnetism, ultrasound, electrical effect, and irradiation; and externally regulated systems, where external stimuli like the pH or enzymes present in the intestinal tract or enzymes present in the drug delivery system control release. This article discusses several systems, such as capsular, osmotic, single- and multiple-unit systems based on soluble or erodible polymer covering and rupturable membranes. It summarizes the most recent technical innovations, formulation parameters, and system release profiles. This study also includes products available as once-daily formulations based on pulsatile releases, such as Pulsincap®, OROS®, CODAS®, and Pulsys®. These systems are helpful for medications with chronopharmacological behavior that need night-time dosage, pharmaceuticals with a first-pass solid action, and a particular location of absorption in the GIT. Diseases wherein PDDS are promising include asthma, peptic ulcer, cardiovascular ailments, arthritis, attention deficit syndrome in children, and hypercholesterolemia. PDDS can potentially bring new developments in the therapy of many diseases.