AN OVERVIEW AND ADVANCEMENT IN OCULAR DRUG DELIVERY SYSTEMS

Eye is most unique organ of the body. Various drug delivery systems are used to deliver drug into eyes are used but there are various limitations of conventional systems so researchers are finding new ways by which contact time, bioavailability and residence time can be enhanced as well as patient discomfort and frequency of dose can be reduced. The conventional dosage forms are account for 90% of currently accessible ophthalmic formulations. The major problem encountered is rapid precorneal drug loss. To improve ocular drug bioavailability, there are significant efforts directed towards newer drug delivery systems for ophthalmic administration. Newer research in ophthalmic drug delivery systems is directed towards a combination of several drug delivery technologies, that includes to develop systems which is not only prolong the contact time of the vehicle at the ocular surface, but which at the same time slow down the elimination of the drug. In this review various new drug delivery systems applied in eye like inserts, in-situ gel, liposomes, niosomes, nanoparticles, iontophorosis, corneal shields, drug embedded contact lenses, ocular wafers and films etc, are discussed.