IN-SITU GELLING SYSTEM: AN ALTERNATIVE CONTENDER FOR CONVENTIONAL DRUG DELIVERY

Abstract

The oral route is among the most often utilized methods for drug delivery however it usually presents the disadvantage of reduced bioavailability due to the first-pass metabolism. Many approaches have been developed to deal with it in which the most popular one is the in-situ gelling system. Formulation based upon in-situ gelling systems has shown numerous advantages like better tolerability, better bioavailability as well as better patient compliance. In-situ gelling systems usually undergo sol-state transition into gel state depending upon the temperature, ion as well as pH condition. The mechanism of the in-situ gel is of three types which are swelling, diffusion and chemical reaction. In the first one, there is the absorption of water due to which there is swelling of the formulation, in the other one there is a precipitation of the polymer in the tissues whereas in the last one there is a formation of the in-situ gel due to the various chemical reactions. Gelling systems are usually classified divided into three groups: systems that are pH, ion, and temperature sensitive. In-situ gelling systems are usually formulated with the help of cross-linking of the co-polymers by numerous approaches. Formulation based upon in-situ gelling system is the best candidate for medication administration owing to its lower dose requirement along with fewer side effects.