Clinical applications of sodium oxybate (GHB): from narcolepsy to alcohol withdrawal syndrome

Gamma-hydroxybutyrate (GHB) is a short chain fatty acid endogenously produced within the central nervous system (CNS) and acts as a precursor and metabolite of the inhibitory neurotransmitter γ-aminobutyric acid (GABA). Although, it is an illegal recreational drug of abuse, its sodium salt (sodium oxybate) has been utilized as a medication for a number of medical conditions. The first aim of this review was to focus on current applications of sodium oxybate for the treatment of narcolepsy, with a particular emphasis on the key symptoms of this disorder: cataplexy and excessive daytime sleepiness (EDS). Secondly, the effectiveness of sodium oxybate therapy for the treatment of alcohol withdrawal syndrome (AWS) and the maintenance of alcohol abstinence has been assessed. Nowadays, sodium oxybate is the first-line treatment for narcolepsy and it is highly effective in meliorating sleep architecture, decreasing EDS and the frequency of cataplexy attacks in narcoleptic patients. Sodium oxybate currently finds also application in the treatment of AWS and the maintenance of alcohol abstinence in alcoholics. Most of the studies evaluating the efficacy of GHB in the treatment of AWS use a dosage of 50 mg/kg divided in three or four administrations per day. Human studies showed that GHB (dose of 50 mg/kg, divided in three administrations per day) is capable to increase the number of abstinent days, reduce alcohol craving and decrease the number of drinks per day. However, there is limited randomized evidence and, thus, GHB cannot be reliably compared to clomethiazole or benzodiazepines. Some randomized data suggest that GHB is better than naltrexone and disulfiram regarding abstinence maintenance and prevention of craving in the medium term i.e. 3-12 months. It is recommended that GHB should be used only under strict medical supervision, since concerns about the abuse/misuse of the drug and the addiction potential have been arisen.