gamma-hydroxybutyrate

enUK

γ-hy·drox·y·bu·tyr·ate (GHB, GHB),

(hī-drok'sē-byū'tir-āt), A naturally occurring short-chain fatty acid, a metabolite of γ-aminobutyric acid (GABA) found in all body tissues, with the highest concentration in the brain. It affects levels of GABA, dopamine, 5-hydroxytryptamine, and acetylcholine, and may itself be a neurotransmitter; accumulation of GHB in people with an inherited disorder in the metabolism of GABA causes ataxia and mental retardation. Synthetic GHB, formerly used in anesthesia and in the treatment of narcolepsy and alcohol withdrawal, has been banned by the U.S. Food and Drug Administration because of severe neurologic, cardiovascular, respiratory, and gastrointestinal side effects. Synonym(s): 4-hydroxybutyrate

Illicit use of GHB has become increasingly popular, particularly among body-builders, because it is easily and inexpensively manufactured in the home and is alleged to suppress appetite, relieve depression, enhance muscle mass by stimulating release of growth hormones, and improve sleep. It has also been used as a euphoriant and (because it is odorless and nearly tasteless and quickly induces sedation with retrograde amnesia) to facilitate date rape. Common street names for GHB include "grievous bodily harm," "liquid ecstasy," "liquid E," "liquid X," and "scoop." The drug is rapidly absorbed after oral administration and readily crosses the blood-brain barrier. It is primarily a central nervous system (CNS) depressant, but also lowers body temperature, heart rate, and cardiac output. Acute toxicity may be manifested by drowsiness, confusion, combative and self-injurious behavior, nausea, tremors, seizures, and coma. The drug acts synergistically with alcohol, benzodiazepines, and narcotics to produce profound CNS and respiratory depression. Most toxic episodes occur in males aged 18-25 and involve alcohol as well as GHB. Habituation is increasingly noted. Frequent dosing (every 1-3 hours around the clock) can induce dependency. Discontinuance after long-term use is associated with a severe withdrawal syndrome including tachycardia, hypertension, tremor, disorientation, hallucinations, and delirium. Treatment of both toxicity and withdrawal is purely supportive. Because the industrial and household solvent γ-butyrolactone (GBL) is metabolized to GHB, it has been marketed illicitly as a nutritional supplement alleged to have the same therapeutic effects as GHB. Its use has been associated with numerous reports of adverse events, including death.