Among the newest drugs available for the treatment of narcolepsy is the chemical gamma hydroxybutyrate (GHB for short), which is also known as sodium oxybate or under the trade name Xyrem. For simplicities sake, I will refer to this chemical by its abbreviated chemical name "GHB". GHB is extremely interesting and promising as a medication, yet, at the same time, controversial as a street drug.
GHB is a neurotransmitter that is naturally present in two regions of the brain called the hypothalamus and the basal ganglia. These regions play a role in sleep, emotion, and movement - all of which are factors in the cataplectic state experience by some people with narcolepsy.
Some scientists believe that symptoms of narcolepsy are the result of REM sleep deprivation since the REM sleep of people with narcolepsy is interrupted by frequent arousals during the night. GHB counteracts these abnormalities by increasing slow wave sleep, lessening stage 1 sleep, and reducing arousals from rapid eye movement (REM) sleep as well as increasing REM efficiency. (Scrima et al, 1990; Fry, 1987; Roth, 1988) The improved quality of nighttime sleep can reduce REM-related symptoms of narcolepsy (such as cataplexy, sleep attacks, sleep paralysis, and hypnagogic hallucination). This ability of GHB to counter sleep abnormalities and narcoleptic symptoms has lead some scientists to a new speculation: at least some of the symptoms of narcolepsy may be caused by impaired natural GHB metabolism. (Patrick, 2003)
GHB can induce a deep sleep quickly, but the effects wear off after 2-4 hours. While GHB can improve sleep and help alleviate REM-related narcolepsy symptoms, it has not been shown to significantly improve daytime alertness. Therefore, a person who has symptoms of excessive daytime sleepiness or sleep attacks may still need to take low doses of stimulants during the day to maintain daytime alertness. (Patrick, 2003; Mamelak, 1981; Scharf et al, 1985) Unlike stimulant drugs and most drugs used to induce sleep, GHB does not seem to lose efficacy after long-term use. In some people, GHB treatment initially intensifies sleep paralysis, sleep attacks, and cataplexy. A rare short-term initial effect in some people is the involuntary discharge of urine. These problems subside after about a week. (Patrick, 2003)
The treatment of narcolepsy using GHB is controversial because it has the potential for being used as a recreational drug of abuse and has also received much negative publicity for being able to be used as a “date-rape" drug.
The FDA gave its approval for GHB to be used to treat symptoms of narcolepsy on July 17, 2002, however there are severe restrictions on the distribution of the medication. Doctors prescribing GHB are required to provide the names and medical progress of patients using GHB to a registry monitored by the FDA. The drug is sent directly to the home of the registered person by Federal Express. (Patrick, 2003) These measures have apparently been put into place in an effort to prevent the diversion of GHB from its medical use to being used as a recreational drug or as a "date-rape" drug. Only one pharmaceutical company has the rights to manufacture GHB for medical use and it distributes the medication under the name Xyrem.
More information can be found at the official Xyrem website: www.xyrem.com.