5. OCULAR DRUG DELIVERY SYSTEM: STRATEGIES TO IMPROVE BIOAVAILABILITY OF THE EYE
Topical eye therapy administration is suitable because of the smaller doses that are needed compared to systemic use, its rapid onset of action and the freedom from systemic toxicity. Because of the blood ocular barrier, the route of choice for treating ophthalmic diseases is by the topical method. Ideal delivery of ophthalmic drugs must be able to withstand the release of the drug and stay close to the front of the eye for extended period of time. The solutions, liquids and ointments which are fairly inefficient as therapeutic systems are the most widely used traditional preparations of ophthalmic dosing types. The efforts lead to the development of novel modes of dosage delivery such as formulations of nanoparticles, liposomes, and niosomes. This analysis based on the controlled and sustained delivery of drugs has become the norm in modern pharmaceutical design and many alternative drug delivery routes into the ocular tissues.