SUSTAINED RELEASE OPHTHALMIC IN-SITU GELS OF DORZOLAMIDE HCl FOR GLAUCOMA-AN APPROACH TO FORMULATION AND IN-VITRO EVALUATION

The objective of the present investigation was to formulate the thermosensitive ophthalmic in-situ gels of Dorzolamide HCl for the treatment of glaucoma. Dorzolamide HCl is presently available as conventional eye drops, which has demerits like pre-corneal elimination, lachrymal drainage and no sustained effect leading to poor bioavailability and hence there was a need to develop a better, stable and sustained drug release dosage form. Dorzolamide HCl loaded thermosensitive ophthalmic in-situ gels were prepared by cold method using poloxamers as thermo-sensitive polymers in different concentrations with HPMC K4M as viscosifier which was used in three different concentrations. A total of six formulations were made and evaluated for para-meters, namely appearance, clarity, pH, gelling capacity, gelation temperature, rheological study, drug content, and in-vitro drug release studies. All the evaluation parameters were within limits. Among all six formulations, one (DF-5) showed the highest drug release, and this formulation was evaluated for sterility, isotonicity, and in-vitro ocular irritation study, where all these parameters were found to be satisfactory. The results of the current study conclude that Dorzolamide HCl in-situ gel is a better alternative approach providing sustained drug release for the management of glaucoma.