A study of percutaneous absorption of estradiol and progesterone in absolute alcohol in postmenopausal women

: Absorption of solutions containing 17-beta-oestradiol (E2) in absolute alcohol and progesterone (P) in absolute alcohol was investigated in six postmenopausal women. These preparations were applied to the skin of the forearm and the abdomen. 1 mg E2 was applied twice daily to the left forearm (RAS) for 28 days. After an interval of one week, the treatment was continued with 1 mg E2 twice daily for 28 days in the epigastric region (RE). From the 14th to the 28th day, this treatment was supplemented by 10 mg P twice daily partly on the right forearm and partly on the epigastrium. The 24-hour absorptions of E2 and P were investigated: E2 on the first and fourteenth days and P on the fourteenth day in both periods. On days 1, 7, 14, 21 and 28, plasma E2, oestrone (E1) and oestrone sulphate (E1SO4) were investigated for hormone application. Statistically significant absorption of E2 was found after 24 hours (p less than 0.05) and significantly greater absorption from RAS than RE (p less than 0.005). No systematic variation in plasma E2 was found during the period of investigation on RAS or RE. P was not absorbed. No local side effects were registered. It is concluded that E2 dissolved in absolute alcohol is clinically employable for treatment of postmenopausal women but that P is of no value in the dosage employed here. Further investigations of transcutaneous absorption of P are desirable.