Drugs for several diseases are still given without regard to the time of the day. Variation in dosing time is generally related with the effectiveness and toxicity of many drugs. On the other hand, several drugs affect the circadian clock. The knowledge of interactions between the circadian clock and drugs is valuable in clinical practice. The pharmacodynamics and pharmacokinetics of the medication influence the chronopharmacological phenomena and recent advances in it have made the traditional goal of pharmaceutics rather outdated. Enhanced progress in chronopharmacotherapy can be achieved if an identification of a rhythmic marker for selecting dosing time is done. However, technology involved in development of drug delivery systems (DDS) that match the circadian rhythm, and the unraveling of the relationship between circardian clock and pathology may be the hindrance in its prosperity for now. The Chronopharmaceutical Drug Delivery System (CDDS) has emerged during the last decade as a possible drug delivery system against several diseases, which may lead to the creation of a sub-disciple of pharmaceutics to be explored called 'chronopharmaceutics'. The review addresses the approaches to this sub-discipline, call attention to potential disease-targets, identifies existing technologies, hurdles and future of chropharmaceuticals. Chronopharmaceuticals coupled with nanotechnology could be the future of DDS, and lead to safer and more efficient disease therapy in the future.
