title: Pediatric zolpidem ingestion demonstrating zero-order kinetics treated with flumazenil.
abstract: Zolpidem is a widely prescribed anti-insomnia agent. Although most pediatric zolpidem ingestions are benign, large ingestions can cause significant central nervous system (CNS) depression. Flumazenil has been reported to reverse the CNS effects of zolpidem. We describe a case of a large pediatric zolpidem ingestion resulting in profound CNS depression that responded to flumazenil administration. Serial zolpidem serum levels confirmed the ingestion. A 10-year-old boy with trisomy 21 presented to the emergency department 1 hour after he was found sedate with several zolpidem 5-mg tablets in his mouth. Seventeen tables (85 mg) were unaccounted for from a prescription bottle. He became unarousable approximately 2 hours after his ingestion. Flumazenil 0.2 mg intravenously was given with rapid return to his baseline mental status. He became resedate 1 hour later but was arousable. Sixteen hours after his presentation, he was asymptomatic. Serial zolpidem serum levels were obtained, showed an initial level of 310 ng/mL, and demonstrated zero-order kinetics. Zolpidem is an imidazopyridine, which binds to the benzodiazepine receptor. It is rapidly absorbed and has a short-half life. Unintentional pediatric ingestions of zolpidem are typically well tolerated. However, this case demonstrates that large ingestions may cause significant and prolonged CNS depression. Flumazenil, a benzodiazepine receptor antagonist, has been described to reverse the effects of zolpidem in adult ingestions. There are few published reports describing flumazenil use in pediatric ingestion patients. This case suggests that flumazenil may be an effective treatment for zolpidem-induced CNS depression in the pediatric patient.
authors.affiliation: From the *Department of Emergency Medicine, University of Kansas Hospital, Kansas City, KS; and †Department of Emergency Medicine, University of California-San Diego; and ‡Department of Emergency Medicine, Naval Medical Center, San Diego, CA.
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Thornton
authors.forename: Elezer
authors.initials: E
authors.lastname: Negus
authors.forename: Shaun D
authors.initials: SD
authors.lastname: Carstairs
mesh_terms: D000931:Antidotes / Q000494:pharmacology / Q000627:therapeutic use*; D002492:Central Nervous System Depressants / Q000097:blood / Q000493:pharmacokinetics / Q000506:poisoning*; D002648:Child; D003128:Coma / Q000139:chemically induced* / Q000188:drug therapy; D004314:Down Syndrome / Q000150:complications; D062787:Drug Overdose / Q000097:blood / Q000188:drug therapy*; D004630:Emergencies; D005442:Flumazenil / Q000494:pharmacology / Q000627:therapeutic use*; D006207:Half-Life; D006801:Humans; D006993:Hypnotics and Sedatives / Q000097:blood / Q000493:pharmacokinetics / Q000506:poisoning*; D008297:Male; D015394:Molecular Structure; D011041:Poisoning / Q000097:blood / Q000188:drug therapy; D011725:Pyridines / Q000097:blood / Q000493:pharmacokinetics / Q000506:poisoning*; D000077334:Zolpidem
chemical_list: D000931:Antidotes; D002492:Central Nervous System Depressants; D006993:Hypnotics and Sedatives; D011725:Pyridines; D005442:Flumazenil; D000077334:Zolpidem