As I mentioned in the April 11 post about narcolepsy, the two main symptoms of narcolepsy are sleepiness and cataplexy. The sleepiness is usually treated with stimulants or Modafinil. Treatment improves the sleepiness, but it usually does not entirely go away.
The stimulants, but not modafinil, also slightly reduce cataplexy.
Cataplexy is " a sudden weakness of the muscles of the body, especially the legs but also the face and neck, that is brought on by strong emotion, especially laughing. " Cataplexy can be very effectively treated by the antidepressants that increase brain levels of norepinephrine, including venlafaxine (effexor), protryptiline (vivactil) and fluoxetine (prozac). (although prozac is a selective serotonin reuptake inhibitor, it has a metabolite that increases norepinephrine).
Xyrem is a novel treatment for cataplexy. Xyrem is gamma hydroxybutyrate (one of the "date rape"/club drugs). It improves night-time sleep, reduces cataplexy, and mildly improves daytime sleepiness. It is FDA approved for the treatment of cataplexy.
From the National Sleep Foundation: This medication is usually administered in two doses, at bedtime and 4 hours later. It produces consolidation of sleep and improvement of disturbed nocturnal sleep characteristic of narcolepsy. This improvement may contribute to decreased daytime drowsiness and diminished cataplexy (Broughton and Mamelak, 1980; Scharf et al.,1985). The dosing makes it very inconvenient to take. Also, because of its history as a date rape drug, it must be ordered from a central pharmacy and mailed to the patient.
In my opinion, Xyrem is faily worthless drug. Cataplexy is usually fairly easy to control with antidepressants. For disturbed night-time sleep in narcolepsy, I prefer to use a hypnotic such as Ambien rather than Xyrem. The only reason to prescribe xyrem, in my opinion, is if someone can not tolerate antidepressants
In my next post about narcolepsy, I will more about how xyrem works, and will also discuss the reconceptualization of narcolepsy from a disorder of sleepiness to a disorder of instability of the sleep/wake systems.