Sleep paralysis can last for a few seconds to a few minutes. In rare cases, hallucinations can occur with sleep paralysis, in which the person sees, hears, feels or tastes something that other people do not.
An episode of sleep paralysis can end on its own or if the person is moved. Even though a person may feel like she cannot breathe during sleep paralysis, the paralysis does not affect the muscles used to breathe.
So what causes sleep paralysis? Health Services at Columbia pointed out that people with narcolepsy often have sleep paralysis. About 250,000 people in the United States have narcolepsy, noted the National Institute of Neurological Disorders and Stroke.
Besides sleep paralysis, patients with narcolepsy experience extreme drowsiness every three to four hours during a 24-hour period and a sudden loss of muscle tone, called cataplexy.
Narcolepsy results from less hypocretin, a type of protein.
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