Objective Physicians often administer intravenous multivitamins to intoxicated patients in the emergency department (ED); however, this practice is not supported by evidence from any prior study. We determined the prevalences of vitamin deficiencies in patients presenting to our ED with alcohol intoxication. Methods This study was a prospective, cross-section, observational study of a convenience sample of ED patients presenting with acute alcohol intoxication. Patients were tested for B 12, folate, and thiamine levels as add-ons to their blood samples. Results Seventy-seven patients were included in the final analysis. The mean age was 46 years, and 19% were female; the mean blood alcohol level was 280 mg/dL. Of 75 patients, no one (0%) had low B 12 or folate levels (95% confidence interval, 0-0.05); 6 (15%) of 39 patients had low thiamine levels (95% confidence interval, 0.06-0.31). Of these 6 patients, none exhibited clinical signs of thiamine deficiency. Conclusions In our ED, patients with acute ethanol intoxication do not have B 12 or folate deficiencies. A significant minority (15%) of patients have thiamine deficiency; its clinical significance is unclear. Widespread administration of multivitamins is unwarranted by these findings, but thiamine may be considered.