Gamma hydroxybutyrate withdrawal

Background

  • Abbreviation: GHB
  • Central nervous system depressant
  • GABA-B agonist (as opposed to GABA-A agonists - alcohol, benzodiazepines, etc)
  • Abused for:
    • Body building or sleep enhancement
    • euphoric, sexual, stimulant, and relaxant effects
    • Surreptitious drugging to facilitate sexual assault
  • Also used therapeutically in the treatment of narcolepsy[1]

Pharmacokinetics

  • effect starts in 15-20min, peaks in 30-60 min,
  • lipid soluble, no protein binding so crosses BBB readily
  • elimination is dose-dependent with half life of 20-50 min
  • The duration of GHB's clinical effects depends upon the dose, and ranges from 2.5 to 4 hours

Pharmacology

  • Is a metabolite and precursor of GABA
  • Interacts with GHB-specific receptors and also acts as a direct agonist of GABA-B receptors
  • Affects multiple neurotransmitter systems, including those of opioids, dopamine, serotonin, glutamate, and acetylcholine
  • Gamma butyrolactone (GBL) and 1,4 butanediol (BD) are GHB analogs that are rapidly metabolized to GHB after ingestion, with the same toxic and recreational effects

Clinical Features

  • Similar to alcohol withdrawal
  • tremor, agitation, hallucinations, tachycardia, hypertension
  • Withdrawal only if have long term use, not episodic binging
    • Occur a few hours after use

Differential Diagnosis

Sedative/hypnotic withdrawal

Evaluation

  • Typically a clinical diagnosis

Management

Disposition

See Also

External Links

References

  1. Mamelak M, Scharf MB, Woods M. Treatment of narcolepsy with gamma-hydroxybutyrate. A review of clinical and sleep laboratory findings. Sleep. 1986;9(1 Pt 2):285-289. doi:10.1093/sleep/9.1.285