The National Sleep Foundation reports:
The Food and Drug Administration’s (FDA) latest drug approval may provide significant symptom relief for narcolepsy patients. Researchers found that Xyrem® (sodium oxybate), a medication approved for treatment of cataplexy (the loss of muscle tone in narcolepsy patients) in 2002, abated symptoms of excessive daytime sleepiness in 4- and 8-week clinical trials. Participants reported a significant improvement in quality of life and the medication was generally well-tolerated. Researchers tested three doses of the drug – 4.5g, 6g, or 9g in divided doses (one at bedtime and the other 2.5 to 4 hours later) in the randomized, double-blind, placebo-controlled trial and found improvement in narcolepsy patients’ reports of excessive sleepiness for the individuals taking the 6g and 9g doses.
Narcolepsy is a neurological disorder caused by the brain’s inability to regulate sleep-wake cycles normally, and its prevalence in the developed world is approximately the same as Parkinson’s disease and multiple sclerosis. Researchers are hopeful that sodium oxybate will provide relief for the disabling effects of excessive daytime sleepiness in narcolepsy patients.
Xyrem has been approved for several years for cataplexy. I have tried to prescribe it several times, but patients find it too inconvenient and don't want to try it. It has to be ordered from a central pharmacy (Another name for Xyrem is gamma-hydroxybutyrate, the "date rape" drug). Also, the patient has to awaken in the middle of the night to take the 2nd dose. From the data I've seen, it is no more effective than the tricyclic antidepressants for cataplexy. And it has the nasty side effect of enuresis (bedwetting).
Its effect on sleepiness is mild- less than the stimulants and provigil. It is thought to decrease sleepiness by improving nocturnal sleep. It consolidates sleep and increases slow wave sleep.
Xyrem may be worth a try in narcoleptics who are having trouble tolerating the traditional medications (stimulants, provigil, antidepressants) used for the symptoms of narcolepsy.