Naloxone-reversible coma unrelated to opiate drugs

A role for endogenous opioids in central nervous system disorders has often been proposed. A case report is presented of a 47-year-old male, medicated only with carbamazepine and lithium, who developed a precipitous alteration of consciousness (Glascow coma scale = 4). An extensive medical workup did not reveal an underlying cause. He exhibited a graded awakening with two intravenous doses of naloxone, which gradually reversed as the last naloxone dose was eliminated. Immunoassay and thin-layer chromatography of two urine samples (to evaluate the possibility of a medication error, alcohol ingestion, or illicit drug use) revealed only the presence of carbamazepine. A dysregulation of the endogenous opioid system is believed to underlie this episode.