To the Editor: The epidemic of recreational use of γ-hydroxybutyrate (GHB; also known as γ-OH) is a cause for concern, as it is a basal anaesthetic agent (ie, it renders the patient unconscious, with analgesic supplementation required for surgery). It is not surprising that people taking too much of it are becoming unconscious.1

GHB was introduced in France as a basal anaesthetic agent by Laborit about 1960. It has a slow onset of action (up to 10 minutes when given intravenously, thought to be due to conversion to an active metabolite, γ-butyrolactone).2 It causes bradycardia, sometimes requiring atropine administration to maintain cardiac output, and raises blood pressure. Respiration is slow and deep, so that alveolar ventilation is not reduced.

Trials of GHB as an anaesthetic were conducted in Melbourne by Dr William Cole and myself in the late 1960s,3-5 and it was used for microlaryngeal surgery for several years. Its major problems were prolonged sleep (1–3 hours after 40–100 mg/kg in children) and a high incidence of postoperative vomiting, adding the danger of aspiration in unconscious patients.

GHB was also tried as an anaesthetic in Dunedin, New Zealand, where it was found that the sleep time could be reduced by intravenous administration of physostigmine.6

The fact that this drug is a basal anaesthetic needs to be more widely publicised.