One hundred and three patients presenting to the Mt. Sinai Medical Center emergency department (ED), who appeared on clinical grounds to be acutely intoxicated, were studied to determine the rate of clearance of ethanol from blood. The mean presenting serum ethanol level was 299 mg/dL. The rate of clearance was found to be 20.43 mg/dL/h with a standard deviation of 6.86 mg/dL/h. No correlation was found between rate of ethanol clearance and serum levels of amylase, alkaline phosphatase, glutamate-oxaloacetate or glutamate-pyruvate transaminase, lactic dehydrogenase, or total bilirubin. Similarly, no correlation was found between rate of clearance and race, sex, age, or time of day. We conclude that although the average patient presenting to the emergency department will clear ethanol at about 20 mg/dL/h, a standard deviation of 6 mg/dL/h means that only 83% of these patients will have clearance rates between 8 and 32 mg/dL/h, and that if accurate estimates are necessary, serial determinations of two or more levels are needed.