Abstract
Transdermal drug delivery system has attracted attention for several advantages over conventional oral or injection route, such as bypassing first–pass effect, safe and painless route, etc., whereas the barrier function of the skin inhibits the drug delivery through the skin. This review focused on transdermal drug delivery system that utilizes ionic liquids (ILs). ILs show the skin penetration enhancing effect by increasing the solubility of drugs, converting lipophilicity of drugs, or by the direct action on the skin structure. We have demonstrated that the incorporation of ILs into emulsion system facilitates the transdermal delivery of poorly soluble drugs and the transcutaneous vaccine delivery.
