Formulation and ex -vivo evalaution of chlorzoxazone transdermal emulgel by skin irritation test

Abstract

Emulgel is one of the recent technologies in NDDS used for dual control release of emulsion and gel for topical use.

Gel formulations generally provide faster drug release compared with conventional ointments and creams.

Chlorzoxazone is a well-known therapeutic agent that is used mainly for its skeletal muscle relaxants. The aim and

objective of the study is to formulate Chlorzoxazone emulgel for topical application. Emulgel of Chlorzoxazone,

consist of Carbopol-940 or HPMCk4 as a gelling agents for gel formulation and tween 80,span 20, for emulsion

formulation. Emulgel was formulated by emulsion incorporated in gel. Chlorzoxazone loaded emulgel was

formulated by using o/w emulsion because of lower solubility in water. Lemon grass oil, Menthol was used as a

penetration enhancer in emulgel formulation. Optimized formulation was evaluated for physical examination,

swelling index, skin irritation study, extrudability study, drug content determination, spreadability, globule size

determination and in-vivo drug release, rheological study. Optimized formulation gave drug release 98.8% for 12 hrs.

The selected gel formulations were found to show no redness of skin and no skin irritation. The formulation was

found to be safe when topically applied.