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Gamma Hydroxybutyrate

(GHB; "G")


Gerald F. O’Malley

, DO, Grand Strand Regional Medical Center;

Rika O’Malley

, MD, Albert Einstein Medical Center

Last full review/revision May 2020| Content last modified May 2020

Gamma hydroxybutyrate causes intoxication resembling alcohol intoxication or ketamine intoxication and, especially when combined with alcohol, can lead to respiratory depression, seizures, and rarely death.

Gamma hydroxybutyrate (GHB) is similar to the neurotransmitter gamma-aminobutyric acid (GABA), but it can cross the blood-brain barrier and so can be taken by mouth. It is similar to ketamine in its effects but lasts longer and is far more dangerous.

GHB produces feelings of relaxation and tranquility. It may also cause fatigue and disinhibition. At higher doses, GHB may cause dizziness, loss of coordination, nausea, and vomiting. Coma and respiratory depression may also occur. Combining GHB and any other sedative, especially alcohol, is extremely dangerous. Most deaths have occurred when GHB was taken with alcohol.

Withdrawal symptoms occur if GHB is not taken for several days after previous frequent use of large amounts. Symptoms are similar to those of alcohol withdrawal and benzodiazepine withdrawal and can be life-threatening.

Treatment is directed at symptoms. Mechanical ventilation may be needed if breathing is affected. Most people recover rapidly, although effects may not fade for 1 to 2 hours.

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