Abstract
Dihydroergotamine (DHE) has recently been suggested as a potential candidate for transdermal administration. In an attempt to increase transdermal delivery of the drug, different enhancers including oleic acid, lauric acid, procaine hydrochloride and urea, were evaluated in vitro, utilizing improved Franz diffusion cells. Oleic acid was found to be the most effective enhancer tested, increasing the percutaneous absorption of DHE by 208-fold. It was found that procaine hydrochloride and lauric acid enhanced transdermal delivery of DHE by 2- and 3-fold, respectively. On the other hand, the formulation containing 6.0% urea did not show any significant difference from the control. The sizable enhancement observed with oleic acid in this study warrants in vivo experimentation with DHE/oleic acid formulations in the future.