Sodium oxybate is a narcolepsy medicine sold under the brand name Xyrem. Sodium oxybate is another name for GHB (gamma hydroxybutyric acid or 4-hydroxybutanoic acid). It is classified as a central nervous system depressant, and in particular it is approved by the FDA for treatment of cataplexy. Some, but not all, narcoleptics get cataplexy which are attacks of sudden loss of muscle tone causing the body to go limp. It can also be used as an anesthetic, but it rarely finds such use in mainstream medicine.
GHB is a naturally occurring neurotransmitter. When a person takes supplemental GHB, it works on both the GHB and GABA receptors in the brain.
Sodium oxybate is taken at night, right before bed. It is a liquid that is mixed with water before swallowing. Many patients take a regimen that involves two dosages every night – spaced 2.5 to 4 hours apart – because of the short half-life. The person has to use an alarm clock to wake up and take their second dose.
Frenquently called SXB in the medical literature, sodium oxybate is a strong sedative and patients are advised against operating heavy machinery or doing anything else that requires them to be wide awake for 6 hours after taking the drug.
This drug acts so fast patients are advised to already be in bed when they swallow it. It is best taken on an empty stomach. SXB produces side effects. The National Library of Medicine lists particularly worrisome side effects as sleepwalking, abnormal dreams, sore throat, fever, chills, and other signs of infection and strongly recommends patients with these symptoms to contact their doctors.
Sodium oxybate helps patients sleep better and the benefits show up as decreased daytime sleepiness on tests and lower tendency to fall asleep during the day as measured by the MSLT. The drug seems to help increase slow wave sleep. More on that here.
The nightly administration of sodium oxybate results in significant reduction in the nocturnal sleep disruption of patients with< narcolepsy.
SXB is designated as an orphan drug in the United States. Nacrolepsy is a rare disease and the drug is not widely prescribed. Drug manufacturer Jazz Pharmaceuticals sponsored clinical trials for SXB use in fibromyalgia treatment. While the drug did seem to have beneiits, the FDA denied approval of expanding the label for sodium oxybate to include fibromyalgia. Doctors may prescribe it for fibromyalgia (and indeed any disorder), but such use would be "off-label". SXB has also been of interest in treatment of schizophrenia (which causes sleep disorders), chronic fatigue syndrome, and certain severe headaches Some patients have experienced weight loss; there is speculation this is due to increased growth hormone. A few high-intensity athletes have used GHB in an attempt to improve their fitness. The increases in levels of human growth hormone may have some connection with the increase in slow-wave sleep.
Like all prescription drugs, SXB should be taken only under a doctor’s supervision. Be sure to tell the doctor about all other drugs you are taking, including over-the-counter medicines and herbal supplements. Users can develop a dependency and have trouble quitting the drug, so many use a tapering regimen. SXB has the potential for abuse; people take it recreationally.
Jazz Pharmaceuticals (the manufacturer) scientists published an article in the Journal of Clinical Sleep Medicine that claims there is low risk of misuse of SXB. This article is probably a response to widespread reports of SXB being used as a date-rape drug. Usually called GHB on the street and by law enforcement personnel, this drug is sometimes administered to victims unknowingly by criminals who want the victim to go unconscious or partially conscious. Date drugs, or club drugs, are notorious. GHB (sodium oxybate) is one of them and even though it has legitimate medical uses, it is subject to stigma.
Jazz Pharmaceuticals was also involved in a court case about how far companies can go with promoting their products. The FDA approves which indications (medical conditions) drugs can be labeled for and for which their makers can advertise them. A salesman for Orphan Medical (later part of Jazz) was caught advocating Xyrem for uses not approved by the FDA. Although doctors are allowed to prescribe drugs off-label, salesmen are not permitted to promote them in that way.