FORMULATION AND EVALUATION OF THERMOREVERSIBLE IN-SITU GEL FOR NASAL ADMINISTRATION

The purpose of present investigation was to formulate nasal in-situ gel drug delivery system of Zolmitriptan which is an antimigraine drug which has an oral bioavailability of 40% with half-life 3 hours. Nasal drug delivery is drug delivery option for challenging clinical situation where common drug administration are inapplicable for drugs with constricted oral bioavailability, due to degradation in the intestinal tract or hepatic first-pass metabolism. Poloxamer 407-a thermoreversible polymer were employed for formulation of in-situ gel along with mucoadhesive polymer HPMC, K4M & carbopol 934. The formulations were prepared by using previously reported cold method and evaluated for appearance, pH, drug content, gelling & gel melting temperature, viscosity studies, % drug content, in-vitro drug release, ex-vivo permeation studies, mucoadhesive strength, gel strength and spreadability. The resultant formulations have percent drug content of 96 -99 %, gelation temperature of 22ºC-44ºC. Viscosities of carbopol containing formulation at 34ºC were low as comparing to formulation containing HPMC, K4M. in-vitro drug release & ex-vivo permeation of optimised formulation F8 is 88.89 % & 75.89% respectively in 8 hours. The mucoadhesive, thermoreversible poloxamer solution of Zolmitriptan for nasal administration could have potential to avoid first pass effect, thus improve bioavailability of drug as a sustained release system to control migraine.