Objective: To develop in-situ ocular gel containing econazole nitrate for the treatment of ocular fungal keratitis with increasing residence time into the cornea for improvement of ocular bioavailability of drug. Experimental work: In-situ ocular gel containing econazole nitrate was formulated by pH responsive method using carbopol 940 as a pH sensitive polymer and different grades of HPMC as viscosifying agent. The formulated batches were evaluated for drug content, pH, gelling time, spreadability, viscosity, gelling strength and in vitro drug release. Stability study was also performed for final formulation. Result and Discussion: The drug content and pH of the formulation were found to be satisfactory. The gelling strength was found to be in the range of 34 seconds to 91 seconds. The viscosity and spreadability of the formulations were found to be satisfactory. All the prepared formulations passed the sterility testing. Formulation F5 containing 0.2 % Carbopol 940 and 0.6 % HPMCK4M showed highest 80.30 % drug release and was stable. The developed formulations showed sustained release of drug up to 8 hrs. From in-vitro drug release studies, it could be concluded that the developed in-situ gelling systems were thus a better alternative to conventional eye drops. Conclusion: The in-situ ocular gel could enhance precorneal residence time with increased viscosity and provided better release profile of drug.
