Alcohol withdrawal syndrome (AWS) may result in nausea, vomiting, diarrhea, weakness, sweating, tremors, tachycardia, hypertension, agitation, delirium, hallucinations, seizures, and death beginning 6 hours after alcohol cessation in alcoholics. Benzodiazepines are cross-tolerant with ethanol and are considered first-line therapy for treating AWS. Chlordiazepoxide and diazepam are first metabolized by hepatic oxidation, then glucuronidation. Lorazepam and oxazepam undergo only hepatic glucuronidation. Benzodiazepine oxidation is decreased in persons with liver disease and the elderly. Accumulation with resultant excessive sedation and respiratory depression may be significant when administering chlordiazepoxide or diazepam to patients with impaired oxidative metabolism. Lorazepam and oxazepam metabolism is minimally affected by age and liver disease. Chlordiazepoxide and diazepam are erratically absorbed by the intramuscular route. Lorazepam is predictably absorbed by the intramuscular route. Oxazepam is not available in parenteral form. Lorazepam appears to be the safest empiric choice among the various benzodiazepines for treating AWS in the elderly and in patients with liver disease, or those who require therapy by the intramuscular route.