Ocular drug delivery is the most fascinating and challenging task faced by pharmaceutical researchers. One of the major barriers of ocular medication is to obtain and maintain a therapeutic level at the site of action for prolonged periods of time. Major problems encountered by conventional ocular dosage forms include rapid pre-corneal drug loss due to naso-lacrimal drainage; tear turnover and ...

Eye is the most vital organ of the body. To achieve effective ocular therapy, an adequate amount of active ingredients must be delivered and maintain at the site of action within the eye. The anatomical structure and the protective physiological process of the eye exert a formidable defense against ophthalmic drug delivery, leads to poor precorneal drug loss results in poor ocular by availabili...

Promising management of eye ailments take off effective concentration of drug at the eye for sufficient period of time. Ocular drug delivery is hampered by the barriers protecting the eye. The bioavailability of the active drug substance is often the major hurdle to overcome. Conventional ocular dosage form, including eye drops, are no longer sufficient to combat ocular diseases. This article r...

Despite numerous scientific efforts many challenges need to be overcome in the ocular delivery because eyes have special and complex anatomic structures. The main problem with the conventional dosage forms is poor ocular bioavailability due to minimum ocular residence time, because of various anatomical and pathophysiological barriers prevailing in the eye. For this reason, much effort has been...

Poor drug delivery to lesions in patients' eyes is a major obstacle to the treatment of ocular diseases. The accessibility of these areas to drugs is highly restricted by the presence of barriers, including the corneal barrier, aqueous barrier, and the inner and outer blood-retinal barriers. In particular, the posterior segment is difficult to reach for drugs because of its structural peculiari...

Several drug delivery systems have been proposed to overcome physiological barriers, improving ocular bioavailability. Systemic routes are seldom used due to the blood-ocular barrier. Novel drug delivery systems based on nanotechnology techniques have been developed to overcome ocular physiological barriers. This non-systematic review suggests the utilization of a transitory blood-ocular breakd...

A variety of ocular drug delivery systems, including a controlled release of the drug, drug targeting, and penetration enhancement of the drug, have been investigated. Biodegradable polymers have been widely used as the drug carrier for controlled-release systems. Biodegradable polymers release the drug as they themselves degrade and are finally absorbed within the body. Several ocular drug del...