The Iontophoretic Transdermal Delivery of Tranexamic Acid

Abstract

It is well known that tranexamic acid (TA) is used as an oral medicine for chloasma. Recently it attracts notice that the external use of TA can also be effective against chloasma and dry-skin. In this study, iontophoresis, which can enhance the efficacy of TA through the facilitation of the transepidermal permeation of the compound, was evaluated. Since TA is an amphoteric substance and becomes various kinds of dissociation status, it is expected that TA shows a complex permeation behavior to the skin. The transepidermal permeation of TA was found to depend on the pH of formulation and the polarity of electrodes. For maximizing the TA concentration in the skin, it was found that (1) the pH of formula should be slightly acidic (around pH 5) and (2) TA should be used on anode upon iontophoresis.