OPHTHALMIC DRUG DELIVERY SYSTEM: AN OVERVIEW

Ideal ophthalmic drug delivery must be able to sustain the drug release and to remain in the vicinity of front of the eye for prolong period of time. Ocular drug delivery is one of the interesting and challenging endeavors facing the pharmaceutical scientist. As an isolated organ the eye is very difficult to study from a drug delivery point of view. Eye drops and eye ointments are conventional ocular dosage forms. They have certain disadvantages like frequent administration, poor availability, massive and unpredictable doses, and drainage of medication by tear and nasolacrimal fluid. Most of ophthalmic drugs are administered topically in the form of eye drops, a dosage form consisting of buffered, isotonic, aqueous solution or suspensions of the drug. Ophthalmic CDDS (controlled drug delivery system) have been mainly prepared as gels, ointments, liposomes, micro and Nanoparticles, micro spheres and ocular minitablets (MT) or films or inserts.