Cataplexy Associated with Narcolepsy

Key points

• Full awareness is kept throughout an episode, the key feature that sets cataplexy apart from a seizure or fainting spell.
• A strong emotion such as laughter or a sudden fright almost always sets off an episode, which usually passes within minutes.
• Clomipramine, a tricyclic antidepressant, dampens the REM-related muscle atonia behind episodes, usually needing several weeks before its full effect appears.

What triggers an episode and how long it lasts

Most episodes last only a few seconds to a couple of minutes and resolve on their own. The emotional trigger is the defining feature: a burst of laughter at a joke, a sudden fright, or even anticipation can be enough. Some people notice a mild warning such as facial twitching or drooping eyelids before muscle control gives way.

Because narcolepsy is often under-recognised, many people live with cataplexy for years before receiving a diagnosis.

Medicines used for cataplexy

The main pharmacological approach is to reduce the frequency and severity of episodes. Clomipramine, a tricyclic agent from the antidepressants category, suppresses REM-related muscle atonia and has been used for cataplexy for several decades. It is typically taken at a low daily dose and may take a few weeks to show full benefit.

If episodes are severe, frequent, or causing injury, a sleep neurologist should be involved in managing the condition alongside any medicines used.

Further reading

• Narcolepsy | National Institute of Neurological Disorders and Stroke
• Narcolepsy - NHS