SUMMARY
Eye is a unique organ which exerts various limitations for the delivery of drug due to its physiology barriers. Therefore, the posterior part of the eyes remains a major concern for formulation scientists to develop ocular drug delivery system which can overcome the barriers of theeye and provide local or systemic effect with immediate or sustained release dosage forms. Conventional ophthalmic dosage forms such as eye drop, ointment and gel provide low bioavailability and less pre-corneal drug residence time due to nasolacrimal drainage of the eyes. The major challenge is to formulate a system to improve the contact time of the drug in eyes. This is achieved by in situ gel system where the drugs are incorporatedwith various types of polymers which exhibit solution to gel phase transition. An in situ gelling technique provides greater bioavailability by resisting ocular drainage leading to longer residence time. This paper proposes the formulation of in situ gels for effective delivery of Erythromycin used to treat conjunctivitis and to evaluate dosage form characteristic such as pH, gelling capacity, gel strength, sterility testing, drug content, in vitro diffusion study, antibacterial activity and accelerated stability studies to ensure the safety and stability of the dosage form. Hence an attempt will be made to develop novel in situ gelling systems using Erythromycin, antimicrobial agent as a promising alternative to the conventional dosage forms for the effective treatment of various eye infections.