Overview on transdermal drug delivery by semisolid systems: Emulgel

Abstract

When gels and emulsions are used in combined form the dosage forms are referred as emulgels. In recent years, there has
been great interest in the use of novel polymers with complex functions as emulsifiers and thickeners because the gelling
capacity of these compounds allows the formulation of stable emulsions and creams by decreasing surface and interfacial
tension and at the same time increasing the viscosity of the aqueous phase. In fact, the presence of a gelling agent in the
water phase converts a classical emulsion into an emulgel. Both oil-in-water and water-in-oil emulsions are used as
vehicles to deliver various drugs to the skin. Emulsions possess a certain degree of elegance and are easily washed off
whenever desired. They also have a high ability to penetrate the skin. Emulgels for dermatological use have several
favorable properties such as being thixotropic, greaseless, easily spreadable, easily removable, emollient, nonstaining,
water-soluble, longer shelf life, bio-friendly, transparent & pleasing appearance.