A 23-year-old comatose man who had drunk an unknown amount of ethylene glycol was admitted to the hospital 5 hours after ingestion. The initial plasma ethylene glycol concentration was 116.2 mg/100 ml. A severe metabolic acidosis was present. Despite aggressive therapy with ethanol, hemodialysis, and intensive care support, the patient died 27 hours after poisoning. The plasma ethylene glycol concentration immediately before death was 35.9 mg/100 ml. Brain edema and acute renal tubular necrosis were evident at postmortem examination. Oxalate crystals were identified in both organs. Ethylene glycol content or concentration was determined in tissues and biologic fluids.