Papaverine and prostaglandin E1 gel applications for impotence.

The transdermal permeability of papaverine and prostaglandin E1 (PGE1) could be determined in vitro. A chemical scheme of passive delivery or with enhancer, as well as a physical iontophoretic transdermal delivery system were designed in the laboratory. Clinically, up to 20% papaverine base gel and 500 micrograms PGE1 were applied onto the genital area without any side effect. Only vascular response could be detected by ultrasound. However, immediate erection could not be obtained at the present dosage. Further research on the combination of skin absorption enhancers, the different chemical derivatives of PGE1 or a different administration route is warranted.