Therapy for Narcolepsy and Cataplexy
REF: Scientific American Medicine October 2003
The initial manifestations of narcolepsy are generally sleep attacks; a classic attack consists of an irresistible desire to sleep in an inappropriate place and under inappropriate circumstances. Attacks generally last from a few minutes to 30 minutes, and the patient feels refreshed on awakening. After months or years, most patients experience cataplexy, during which they transiently lose muscle tone (e.g., sagging of the head, drooping of the eyelids, and buckling of the knees). Cataplexy is often triggered by a sudden emotional outburst. The patient may momentarily collapse and fall to the ground or may simply slump forward for a few seconds before regaining awareness.
The administration of a stimulant (e.g., modafinil, methylphenidate, dextroamphetamine, methamphetamine, or pemoline) is the treatment of choice for narcoleptic sleep attacks.1 In newly diagnosed patients, the drug most commonly used initially is modafinil, a novel wakefulness-promoting agent, or methylphenidate. Dextroamphetamine and methamphetamine are used in those patients who do not respond satisfactorily to these stimulant drugs. Because of hepatotoxicity, pemoline is now rarely used.
Tricyclic antidepressants (e.g., protriptyline, imipramine, clomipramine) and selective serotonin reuptake inhibitors (e.g., fluoxetine) are used to treat cataplexy or other auxiliary symptoms of narcolepsy. Recently, sodium oxybate (Xyrem)more commonly known as g-hydroxybutyric acid-has been approved for treatment of cataplexy. An endogeneous hypnotic, sodium oxybate acts by consolidating REM and slow wave sleep. The medication is given at bedtime and, often, with an additional dose later at night. Taking short daytime naps and joining narcolepsy support groups can be useful approaches as well.
1. Overeem S, Mignot E, Van Dijk, et al: Narcolepsy: clinical features, new pathophysiologic insights and future perspectives. J Clin Neurophysiol 18:78, 2001 [PMID 11435802]
Drug for excessive sleepiness: Provigil (Modafinil)
Armodafinil 150 mg before each night shift significantlh improved wakefulness
in patients with excessive sleepiness during scheduled night work, associated
with chronic SWD (Shift Work Disorder). It significantly improved measures
of overall clinical condition, longterm memory, and attention.
Ref: Mayo Clin Proc Nov 2009;84(11):958