Preparation and in vitro evaluation of emulgel formulations containing topical corticosteriod

Topical corticosteroids are widely used in the treatment of skin conditions such as eczema, seborrheic eczema, psoriasis due to their anti-inflammatory, antiproliferative and immunosuppressive effects. Diflucortolone valerate (DFV) is a potent glucocorticoid that belongs to Class III topical corticosteroids. Commercial preparations are available in the form of cream and pomade. Lipophilic character and poor water solubility of DFV limit loading of the active substance into a water-based drug delivery system. Stratum corneum forms an important barrier for the release of topical drugs from the formulation, their permeation through the skin and their penetration into tissues. The physicochemical properties of active and excipient substances, the physiological conditions of the skin also significantly affect the permeation through the skin. Penetration enhancers can be added to formulations to improve bioavailability in topical preparations. Emulgels are the topical drug delivery systems which are prepared using water-in-oil or oil-in-water emulsions and gel forming agents. Having the advantages of emulsions and gels, emulgels allow the hydrophobic and hydrophilic active ingredients to be loaded and provide controlled release of the active substance from the formulation. Within the scope of this study, emulgel formulations of DFV with lipophilic properties were prepared using different penetration enhancing agents and in vitro release studies were carried out with optimum formulations evaluated in terms of physicochemical parameters. The results obtained from the optimum emulgel formulations showed that there was an increase in the cumulative release of DFV compared to the commercial preparation.