In general, patients feel exhausted all the time and would fall asleep as soon as they are not moving or being stimulated (for example as a passenger in a car). Sleepiness is the most problematic symptom in narcolepsy. Only after many months the cataplexy starts then to transform into the “adult” form only triggered by jokes or laughing. Children can also feel generally weak, having trouble walking.

Although cataplexy is most often triggered by emotions such as a good joke or a funny cartoon, in children close to onset, it can be atypical and manifest by mouth opening, jaw dropping with tongue protrusions that are not always obviously triggered by emotions. Reflexes are abolished during the attack. In severe cases, the patient might fall and become completely paralyzed for a few seconds to several minutes. In other typical cataplectic attacks, the head may drop or the jaw may become slack. Typically, the patient's knees buckle and may give way upon laughing, elation, surprise, or anger. Cataplexies are sudden, brief episodes of muscle weakness triggered by emotions. Indeed, patients with narcolepsy enter REM sleep abnormally fast, minutes after falling asleep unlike normal people where REM sleep only appear after one hour of sleep (see History of Narcolepsy).Ĭataplexy is unique to NT1.

Since the 1960s it has been known that several of the disabling symptoms of narcolepsy, such as sleep paralysis, cataplexy and hypnagogic hallucinations, are pathological equivalents of REM sleep (a stage of sleep when we dream but are paralyzed to avoid moving in our dreams). A rapid gain of weight often also occurs.

About half of all patients start narcolepsy before age 18, in rare cases as young as 3 years old, and in general the younger it starts, the more severe and abruptly the disease strikes in young children one often observed a regression where tantrums and bad behavior restarts because the child is always exhausted. It affects about 0.03% of the population (1 for 3,000 individuals) in most countries in the world. The main symptoms of narcolepsy type 1 (NT1) are excessive daytime sleepiness, cataplexy, sleep paralysis, hypnagogic hallucinations, and disturbed nocturnal sleep.

Cataplexy causes