Shweta Pandey, Niraj, M.M. Gupta, Manish Jamini
Conventional dosage forms such as tablets, capsules, gels etc. immediately provide drug delivery and it cause fluctuation of drug level in blood. So for maintaining drug concentration within therapeutic effective range and to deliver drug at specific site now a days target drug delivery system is one of the most considerable novel approach towards drug delivery system. Targeted drug delivery seeks to concentrate the medication in the tissues of interest while reducing the relative concentration of the medication in the remaining tissues thus improving therapeutic index and bioavailability at site specific-delivery . This improves efficacy of the drug while reducing side effects. New drug delivery systems include lipidic, surface active agents, proteic and polymeric technologies to provide new sustained drug delivery with better body distribution, drug protection from the harsh ex-ternal environment and avoidance of drug clearance. Now a days various carrier systems such as liposomes, niosomes, aquasomes, pharmacosomes, dendrimers, nanoparticles, microspheres, solid lipid nanoparticles, resealed erythrocytes etc. are used in target drug delivery system which provide site specific drug delivery. Target drug delivery system is used in various diseases where it is very difficult for a drug molecule to reach its destination in the complex cellular network of an organism.
