THE EFFECTS OF ETHANOL ON THE CLEARANCE OF ESTRADIOL IN POSTMENOPAUSAL WOMEN

Objective: To determine whether acute alcohol ingestion affects the pa ttern of decline of circulating E(2) levels after removal of transderm al E(2) patches.Design: A randomized, placebo-controlled, crossover st udy. Setting: The study was performed in the Clinical Research Center of the Brigham and Women's Hospital. Participants: Twelve healthy post menopausal women were enrolled. Interventions: Transdermal E(2) patche s, 0.15 mg, were applied 13 hours before subjects ingested alcohol (1 mL/kg 95% ethanol) or carbohydrate placebo punch. The patches were rem oved immediately after drink ingestion. Main Outcome Measures: Estradi ol, estrone (E(1)), and ethanol levels were measured. Results: Serum s amples were obtained for 40 minutes before drink ingestion and 5 hours after drink ingestion and E(2) patch removal. At the time of patch re moval, E(2) levels rose acutely over 10 minutes and then decreased rap idly, suggesting a bolus effect that was more marked after ethanol ing estion. After ethanol ingestion and patch removal the half-life of E(2 ) was calculated to be 378 minutes, and after carbohydrate punch and p atch removal 245 minutes. There were no significant changes in E(1) co ncentrations over the time course of the study between groups. Conclus ions: Ethanol ingestion may decrease E(2) clearance after removal of t ransdermal E(2) patches.