A patient in their 40s with poorly controlled diabetes, including prior episodes of diabetic ketoacidosis; chronic pancreatitis; gastroparesis; depression; and polysubstance abuse was found obtunded and then unresponsive by a family member. Emergency medical services recorded a blood glucose level of 250 mg/dL (normal range of fasting blood glucose, 80-100 mg/dL; to convert to mmol/L, multiply by 0.0555). The patient received 2 mg of naloxone intramuscularly without any effect. In the emergency department, the patient had a Glasgow Coma Scale score of 3 and was tachycardic, hypotensive, and had dilated pupils. The patient had a brief episode of tonic-clonic seizure-type activity and was then emergently intubated for airway protection and received fluid resuscitation.