Percutaneous absorption of hydrocortisone and testosterone on the vulva and forearm: effect of the menopause and site.

The percutaneous absorption of hydrocortisone and testosterone was studied following their application to the vulvar and ventral forearm regions of pre- and post-menopausal women. Percutaneous absorption of hydrocortisone was significantly greater in vulvar skin than forearm skin in both pre- and post-menopausal women (P < 0.05, respectively), whereas the percutaneous absorption of testosterone was significantly increased (P < 0.01) on the vulva compared with the arm only in post-menopausal women. The effect of age on the percutaneous absorption of hydrocortisone and testosterone was evaluated by using the menopause as a biological chronometric end point. It is a common misconception that older skin has a diminished barrier capacity, and that percutaneous absorption is therefore greater. Our studies showed that absorption of hydrocortisone vulval skin of pre-menopausal women was significantly greater (P < 0.01) than in post-menopausal women. The ventral forearm skin of pre-menopausal women tended to show increased absorption compared with post-menopausal women, but statistical significance was not reached. No significant differences (P > 0.05) in the percutaneous absorption of testosterone in vulval or forearm skin were observed between the two age groups.