Cataplexy

Cataplexy
Classification and external resources
ICD-10	G47.4
ICD-9	347
DiseasesDB	16311
MeSH	D002385

Cataplexy is a sudden and transient episode of loss of muscle tone, often triggered by emotions. It is a rare disease (prevalence of fewer than 5 per 10,000 in the community), but frequently affects people who have narcolepsy, a disorder whose principal signs are EDS (Excessive Daytime Sleepiness), sleep attacks, sleep paralysis, hypnagogic hallucinations and disturbed night-time sleep. Cataplexy is sometimes confused with epilepsy, where a series of flashes or other stimuli cause superficially similar seizures. Cataplexy can also be present as a side effect of SSRI Discontinuation Syndrome.

The term cataplexy originates from the Greek κατά (kata, meaning "downwards"), and πληξις (plēxis, meaning "paralysis").

Presentation

Cataplexy manifests itself as muscular weakness which may range from a barely perceptible slackening of the facial muscles to the dropping of the jaw or head, weakness at the knees, or a total collapse. Usually the speech is slurred, vision is impaired (double vision, inability to focus), but hearing and awareness remain normal. These attacks are triggered by strong emotions such as exhilaration, anger, fear, surprise, orgasm, awe, embarrassment, and laughter. A person's efforts to stave off cataplectic attacks by avoiding these emotions may greatly diminish their lives, and they may become severely restricted emotionally if diagnosis and treatment is not begun as soon as possible.

Cataplexy may be partial or complete, affecting a range of muscle groups, from those controlling facial features to (less commonly) those controlling the entire body.

• Arm weakness
• Sagging jaw
• Drooping head
• Slumping of the shoulders
• Slurred speech
• Generalized weakness
• Knee buckling

When cataplexy happens often, or cataplexy attacks make patients fall or drop things, it can have serious effects on normal activities. It can cause accidents and be embarrassing when it happens at work or with friends. For example, people with cataplexy may not pick up babies because they are afraid they may drop them.

Treatment

Despite its relation to narcolepsy, in most cases, cataplexy must be treated differently and separate medication must be taken. For many years, cataplexy has been treated with tricyclic antidepressants such as imipramine, clomipramine or protriptyline. However these can have unpleasant side-effects and so have been generally replaced by newer drugs such as venlafaxine, a more recent antidepressant.

A treatment option for cataplexy associated with narcolepsy is Xyrem (sodium oxybate) oral solution. Xyrem is a prescription medication manufactured by Jazz Pharmaceuticals, and is approved by the U.S. Food and Drug Administration (FDA) for the treatment of cataplexy associated with narcolepsy and Excessive Daytime Sleepiness (EDS) associated with narcolepsy . The American Academy of Sleep Medicine (AASM) recently recognized Xyrem as a standard of care for the treatment of cataplexy, daytime sleepiness, and disrupted sleep due to narcolepsy in its Practice Parameters for the Treatment of Narcolepsy and other Hypersomnias of Central Origin. These recommendations are based upon careful review of the medical literature, and the designation “standard” of care “reflects a high degree of clinical certainty” based on strong empirical evidence. Xyrem is the only medication specifically indicated and approved by the U.S. Food and Drug Administration (FDA) for cataplexy associated with narcolepsy.

Monoamine oxidase inhibitors may be used to manage both cataplexy and the REM sleep-onset symptoms of sleep paralysis and hypnagogic hallucinations.

Emerging Therapies

Emerging therapies include Hypnotic Psychotherapy, Hypocretin Gene Therapy, and Hypocretin Cell Transplantation for narcolepsy-cataplexy. See http://www.journalsleep.org/Articles/280612.pdf and http://www.thefreelibrary.com/Two+Patients+with+Narcolepsy+Treated+by+Hypnotic+Psychotherapy.-a0229530414]

Diagnosis

Cataplexy in severe cases can cause vital signs to be hard to detect without a continuous auditory pulse oximeter. As an anecdotal example, Allison Burchell, a sufferer of severe cataplexy, has been pronounced dead three times.

See also

• Neurodegenerative disease
  • Niemann Pick disease

In the media

• Recently, The Learning Channel (TLC) aired an episode of "My Shocking Story: I Woke Up in a Morgue" which detailed several cases of cataplexy.
• On Tuesday, August 5, 2008 BBC News ran a story about a young woman who collapses when she laughs, in attempts to raise awareness about cataplexy.
• On Friday, June 4, 2010 radio series This American Life (TAL) ran an act on Matt Frerking detailing his cataplexic disorder.

External links

• Narcolepsy Association UK
• BBC's Article on the condition
• National Niemann Pick Disease Foundation: Children with Niemann Pick Type C often suffer from cataplexy
• Video of patient with cataplexy
• This American Life episode that interviews someone with narcolepsy with cataplexy

af:Katapleksie tr:Katapleksi