Abstract

PATIENT COMPLIANT OCULAR IN SITU GELLING SYSTEM OF AZITHROMYCIN DIHYDRATE

Ganesh S. Deshmukh* and D. S. Rathore

Abstract

Gelation of sodium alginate and Carbopol caused by change in pH of the solution has been applied to develop an ophthalmic formulation of azithromycin dihydrate, in the present study. Rapid spill out of drug on instillation into cul de sac would be minimal with in situ gelling ophthalmic solution leading to increased precorneal adherence time and prolonged drug delivery, and hence increase bioavailability. In the formulation development studies sodium alginate was used in different concentrations (0.5-2% w/v) and different proportions of the Carbopol® 980 were used. The primary criteria for formulation optimization were gelling capacity and rheological behaviour and antimicrobial efficacy and drug release. The clarity, pH, gelation power in simulated tear fluid and rheological properties of the optimized formulations were satisfactory. The formulations inhibited the growth of Staphylococcus aureus Gram Positive and Pseudomonas aerugenosa Gram Negative effectively in cup–plate method and were proved to be safe and non irritant on rabbit eyes. The results indicate that sodium alginate and Carbopol based in situ gels can be successfully used to prolong the duration of action of azithromycin dihydrate.

Keywords: Azithromycin dihydrate, in situ ocular gel, pH-induced gelation, sodium alginate, Carbopol.