Pentobarbital for severe gamma-butyrolactone withdrawal

Study objective: Gamma-hydroxylbutyrate (GHB) and gamma-butyrolactone (GBL have become popular drugs of abuse. Acute overdose with either agent result s in a well-recognized syndrome of central nervous system and respiratory d epression. Recently, a withdrawal syndrome has been described for GHB. We r eport 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 with drawal in a regional toxicology treatment center. Results: During a 6-month period, 5 patients presented with severe withdraw al attributed to abrupt GBL discontinuation. Patients manifested tachycardi a, hypertension, paranoid delusions, hallucinations, and rapid fluctuations in sensorium. Test results for ethanol and routine drugs of abuse were neg ative. Initial treatment with high doses of lorazepam proved ineffective, P entobarbital was then administered, resulting in excellent control of behav ioral, autonomic, and psychiatric symptoms and in rapid reduction or avoida nce of benzodiazepines. Median hospital stay was 5 days. No patient had res piratory depression or required mechanical ventilation. Patients were disch arged on tapering doses of benzodiazepines or pentobarbital and were free o f psychotic symptoms at follow-up. Conclusion: GBL discontinuation can result in severe withdrawal, necessitat ing ICU admission. Pentobarbital may be more effective than benzodiazepines at controlling delirium in patients with abnormal vital signs, paranoid de lusions, and hallucinations as a result of GBL withdrawal.