BACKGROUND AND PURPOSE: Heavy binge drinking may trigger the onset of embolic stroke and acute myocardial infarction, but the underlying mechanisms are unclear. The effects of binge drinking on the hemostatic system and its circadian variation have not been investigated. We investigated the effects of an acute intake of a large dose of alcohol (1.5 g/kg). METHODS: Twelve healthy, nonsmoking men participated in sessions where they were served ethanol in fruit juice or served fruit juice alone and, lying in a supine position, were followed up for 12 to 24 hours. The treatments were randomized and separated from each other by a 1-week washout period. Blood and urine were collected for hemostatic measurements. RESULTS: The urinary excretion of the platelet thromboxane A(2) metabolite 2, 3-dinor-thromboxane B(2) was significantly (P