Transdermal delivery systems which are directly applied on the skin serve as a substitute for oral drug delivery avoiding first-pass metabolism. The problem of drug penetration through the skin definitely remains one of the biggest issues. This study ascertains the likelihood of DMSO, a penetration enhancer to boost KT, one of the most powerful analgesics. Through DMSO amount variations on KT were prepared and then permeation was studied by means of a Franz Diffusion cell system on rat skin. It increased the permeability coefficient and flux with the increase of the DMSO level, and it reached the maximum when the DMSO concentration was 0. 1. Further understanding of mechanisms and optimal DMSO concentrations seem to be necessary for future development of this promising anticancer treatment approach. Briefly summarizing, DMSO does seem to meet the demands, according to the transdermal drug delivery efficacy standpoint, being safe and convenient for topical application.