GHB Overdose

“Patients who take an overdose of GHB present with a remarkably diminished level of consciousness. Hypothermia, bradycardia, vomiting, and hypotension are other manifestations. In a recent report of several patients who presented with GHB overdose, all were noted to have delirium and transient respiratory depression.
Use of physostigmine should be considered carefully because of its potential dangers. Physostigmine may exacerbate bradyarrhythmias and atrioventricular conduction delays. Seizures have been reported with rapid administration. In addition, its use may precipitate bronchospasm, vomiting, defecation, urination, and excessive salivation (cholinergic crisis).
In light of the potential toxicity of physostigmine, it should be used only in patients in whom GHB ingestion is certain, and physostigmine should be administered slowly (over 2-5 minutes) and intravenously. Physostigmine dose is 2 mg.”
— Mayo Clin Proc 2000