Effect of alcoholic beverages on the pharmacokinetics of doxycycline in man

In a randomized cross-over trial on six healthy medical students, alcohol (lg/kg) ingested as whisky did not modify significantly the absorption of 200 mg of doxycycline (DC) given in two tablets. Cheap red wine with a clear taste of acetic acid postponed the absorption of DC for 2-3 hours without affecting its 24-hour AUC or urinary excretion significantly. Another similar trial with other wines on 8 healthy students suggested that good regular wines do not retard DC absorption irrespective of their tannic acid content. However, acetic acid may postpone DC absorption by possibly slowing the rate of gastric emptying.