Drug misuse, intoxication and withdrawal Quiz: Ace Your Exams

A 58-year-old man is brought to the emergency department to evaluate nausea, slurred speech, and altered level of consciousness. Past medical history includes alcohol use disorder, type 2 diabetes mellitus, benign essential tremor, intravenous drug use, chronic pain, and depression. Medications include metformin, primidone, methadone, and escitalopram. The patient’s spouse reports the patient has been particularly depressed after the recent death of his mother. While awaiting evaluation, the patient suddenly becomes unresponsive. Temperature is 37.3°C (99.2°F), pulse is 115/min, respirations are 13/min, and blood pressure is 89/58 mmHg. Physical examination reveals a lethargic patient who localizes to pain in response to sternal rub. The pupils are 3 mm bilaterally and reactive to light. Laboratory results are shown below. The patient is subsequently intubated and admitted to the intensive care unit. Twenty-four hours later, the patient does not pass spontaneous breathing trials for extubation. Which of the following substances is the most likely etiology of this patient’s current condition?  

Laboratory value	Result
Sodium	140 mEq/L
Potassium	4.1 mEq/L
Chloride	102 mEq/L
HCO3-	24 mEq/L
Serum
Creatinine	0.6 g/dL
BUN	10 mg/dL
Glucose	120 mg/dL
Alcohol	300 mg/dL