['To determine the association of ethanol intoxication with hypoglycemia in ED patients.', 'Retrospective, laboratory log review of 953 consecutive patients who were evaluated for ethanol intoxication in an urban university hospital ED over a three-month period. Simultaneous serum glucose determination was carried out for each patient and associations between ethanol level and glucose were sought.', 'Glucose concentrations were unavailable for 16 patients (1.7%). Of the remaining patients, 584 patients had detectable ethanol concentrations (ethanol-positive), and 353 had no detectable ethanol (ethanol-negative). Ethanol concentrations (mean +/- SD) in the ethanol-positive group were 50.11 +/- 24.08 mmol/L (231 +/- 111 mg/dL), and glucose concentrations were 5.83 +/- 1.94 mmol/L (105 +/- 35 mg/dL). Hypoglycemia [glucose < 3.72 mmol/L (67 mg/dL)] was observed for five (0.9%) ethanol-positive patients. It was classified as mild-moderate [2.78-3.66 mmol/L (50-66 mg/dL)] for four patients (0.7%) and severe [< 2.78 mmol/L (50 mg/dL)] for one (0.2%). Ethanol concentrations ranged from 25.60 to 68.33 mmol/L (118 to 315 mg/dL). There was no correlation between ethanol and glucose concentrations in any subset of the ethanol-positive patients population. In the ethanol-positive group, patients who had several ethanol-positive visits (56 patients, mean 3.6 visits/patient) accounted for four of the five episodes of hypoglycemia, including the one episode of severe hypoglycemia. The frequency of hypoglycemia in repeat visitors (2.0%) was higher than that in the group of patients without repeat visits (0.2%). In the ethanol-negative group, there were four (1.1%) episodes of mild-moderate hypoglycemia and no severely hypoglycemic patients. Hypoglycemia was not more likely to occur among ethanol-positive patients than it was among ethanol-negative patients.'] Is ethanol-associated hypoglycemia uncommon?