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Gammahydroxybutyrate overdose and physostigmine

Three Part Question

In [patients with gammahydroxybutyrate ingestion] does [treatment with physostigmine] [reduce the neccessity for intubation and duration of unconsciousness]?

Clinical Scenario

A 25 year old man is brought to the Emergency Department after collapsing in a club. His friends report ingestion of Gammahydroxybutyrate (GHB) and alcohol. His Glasgow Coma Scale score is 3 on arrival and he is intermittently apnoeic. When you attempt to intubate him he seems to rouse but quickly becomes unresponsive again once you stop. You ask for anaesthetic help. The anaesthetic registrar has a similar experience on attempting intubation. You are sure you have read that physostigmine can be used to avoid intubation in this situation. You wonder if you have remembered correctly.

Search Strategy

MEDLINE using the OVID interface 1966 to January Week 1 2006
Embase using the OVID interface 1980 to 2006 Week 02
The Cochrane Library Issue 4 2005
OVID:[exp Hydroxybutyrates/ OR OR] AND [ or exp Physostigmine/] Limit to Humans and English Language
Cochrane:[Hydroxybutyrates {MeSH explode all trees} OR gammahydroxybutyrate {all fields}] AND [physostigmine {MeSH explode all trees}]

Search Outcome

18 papers were found of which 1 was a systematic review. All other relevant papers were included in the review.

Relevant Paper(s)

Author, date and country Patient group Study type (level of evidence) Outcomes Key results Study Weaknesses


As noted in the review by Traub et al, the evidence for and against the use of physostigmine is of poor quality. Only 2 papers (involving 6 patients) are set in the Emergency Department, while those in the anaesthetic room are uncontrolled. This matters since the recovery from GHB induced anaesthesia is relatively rapid and it is therefore difficult to draw conclusions from uncontrolled studies.

Clinical Bottom Line

The evidence for the use of physostigmine is of low quality. Local advice should be followed.


  1. Traub S. Physostigmine as a treatment for Gamma Hydroxybutyrate Toxicity: A Review. Journal of Toxicology 2002, vol 40, No 6 p 781-7.