GHB (Gamma-Hydroxybutyric Acid)
Definition
An endogenous GABA metabolite and short-chain fatty acid; exogenous doses of 1-3 g produce sedation, euphoria, and amnesia. Blood half-life ~20-30 min; urine detection window 8-12 hours post-ingestion. Pharmaceutical sodium oxybate (Xyrem) is FDA-approved for narcolepsy.
- Endogenous role
- Naturally occurring GABA metabolite
- Exogenous dose effect
- 1-3 g: sedation, euphoria, amnesia
- Blood half-life
- ~20-30 minutes
- Urine detection window
- 8-12 hours post-ingestion
- FDA-approved form
- Sodium oxybate (Xyrem) for narcolepsy
Common questions
Why is GHB particularly hard to detect in suspected drug-facilitated assault cases?+
Its short half-life and narrow detection window mean that by the time a victim is tested, the compound may already be below detectable levels, and because it also occurs naturally in the body, low concentrations can be hard to interpret.
How is GHB related to GBL and 1,4-butanediol?+
GBL (gamma-butyrolactone) and 1,4-butanediol are precursor chemicals that convert to GHB once ingested, so both can produce the same pharmacological and toxicological effects even though they are chemically distinct compounds.
What helps distinguish a GHB overdose from normal endogenous levels?+
Because GHB is naturally present at low concentrations, labs rely on established cutoff concentrations and case context, such as coexisting depressant effects or postmortem interval, rather than mere presence alone.
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