title: Pentobarbital for severe gamma-butyrolactone withdrawal.
abstract: OBJECTIVE
  Gamma-hydroxybutyrate (GHB) and gamma-butyrolactone (GBL) have become popular drugs of abuse. Acute overdose with either agent results in a well-recognized syndrome of central nervous system and respiratory depression. Recently, a withdrawal syndrome has been described for GHB. We report a severe form of GBL withdrawal, characterized by delirium, psychosis, autonomic instability, and resistance to benzodiazepine therapy.
  
  
  METHODS
  We performed a chart review of consecutive admissions for GBL withdrawal in a regional toxicology treatment center.
  
  
  RESULTS
  During a 6-month period, 5 patients presented with severe withdrawal attributed to abrupt GBL discontinuation. Patients manifested tachycardia, hypertension, paranoid delusions, hallucinations, and rapid fluctuations in sensorium. Test results for ethanol and routine drugs of abuse were negative. Initial treatment with high doses of lorazepam proved ineffective. Pentobarbital was then administered, resulting in excellent control of behavioral, autonomic, and psychiatric symptoms and in rapid reduction or avoidance of benzodiazepines. Median hospital stay was 5 days. No patient had respiratory depression or required mechanical ventilation. Patients were discharged on tapering doses of benzodiazepines or pentobarbital and were free of psychotic symptoms at follow-up.
  
  
  CONCLUSIONS
  GBL discontinuation can result in severe withdrawal, necessitating ICU admission. Pentobarbital may be more effective than benzodiazepines at controlling delirium in patients with abnormal vital signs, paranoid delusions, and hallucinations as a result of GBL withdrawal.
authors.affiliation: Department of Emergency Medicine, University of Massachusetts Medical School, Worcester, MA, USA. sivilotm@meds.queensu.ca
authors.forename: M L
authors.initials: ML
authors.lastname: Sivilotti
authors.forename: M J
authors.initials: MJ
authors.lastname: Burns
authors.forename: C K
authors.initials: CK
authors.lastname: Aaron
authors.forename: M J
authors.initials: MJ
authors.lastname: Greenberg
mesh_terms: D015107:4-Butyrolactone / Q000009:adverse effects*; D000328:Adult; D001143:Arousal / Q000187:drug effects; D001342:Autonomic Nervous System Diseases / Q000139:chemically induced* / Q000188:drug therapy; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D013287:Illicit Drugs / Q000009:adverse effects*; D008297:Male; D010424:Pentobarbital / Q000627:therapeutic use*; D011605:Psychoses, Substance-Induced / Q000188:drug therapy*; D013375:Substance Withdrawal Syndrome / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D013287:Illicit Drugs; D010424:Pentobarbital; D015107:4-Butyrolactone