Ocular drug delivery system: Approaches to improve ocular Bioavailability
There is a lots of route of drug delivery, but today one of them, the ocular drug delivery system becomes the most compulsive and attractive attempt in front of pharmaceutical scientists. Ocular drug delivery has always been a formidable task in the area of pharmaceutical research due to distinctive structure and function of the eye. Different attempt in ocular drug delivery have been made to enhance the bioavailability and to increase the contact time of topically applied drugs to the eye. In an ophthalmic dosage form the less bioavailability is due to the tear production, achieving less absorption, short term residence time, and less permeability of corneal epithelium. Immediate pre-corneal elimination is a biggest problem in ocular drug delivery. In order to solve this problem, researchers developed a new system; in-situ gel forming system. This formulation undergoes phase transition in the eye to form gel, thus prolonging the precorneal contact time which will result in enhance ocular bioavailability for prolonged therapeutic action ointment, suspensions and gelled systems are also used.