Gamma butyrolactone (GBL) is an increasingly popular drug of abuse that is readily available in most countries, and it is often purchased over the Internet. In addition to the acute hazards of intoxication and overdose, users who are dependent on GBL can also experience severe withdrawal reactions, including hallucinations, agitation, confusion, delusions, delirium, rhabdomyolysis, and seizures. Most of the existing literature suggests the use of a high-dose benzodiazepine as a first-line treatment for GBL withdrawal. However, several cases of resistance to benzodiazepines have been observed, which likely reflect some pharmacological differences between benzodiazepines and GBL. Specifically, the effects of benzodiazepines are primarily mediated by gamma-aminobutyric acid (GABA)-A receptors, while GBL and its analogues act mainly at GABA-B receptors, with possible additional effects via the ionotropic GABA-A receptors. In this regard, recent studies have found that GBL and its analogues possess a high affinity for a specific form of extrasynaptic GABA-A receptors that are strongly activated by barbiturates, such as phenobarbital, but that are insensitive to benzodiazepines. Taken together, these findings suggest that barbiturates could be evaluated as first-choice agents for the treatment of GBL/gamma hydroxybutyrate (GHB) withdrawal instead of benzodiazepines. In support of this view, we describe a clinical case of difficult to manage GBL withdrawal symptoms in a 42-year-old male. We also review the literature on treatment options for GBL/GHB withdrawal, including benzodiazepine-resistant withdrawal. (Journal of Psychiatric Practice 2014;20: 294–300)
GHIO, CERVETTI, RESPINO, and AMORE: University of Genoa, Italy; MURRI: University of Parma, Italy.
The authors declare no conflicts of interest
Please send correspondence to: Lucio Ghio, Department of Neuroscience, Ophthalmology and Genetics, Psychiatry Section, University of Genoa, Largo Rosanna Benzi 10, 16100 Genoa, Italy. firstname.lastname@example.org