Narcolepsy is a chronic sleep disorder that causes people to fall asleep during the day at random. People can feel drowsy and experience hallucinations, sleep paralysis, and in severe cases, cataplexy (partial or complete loss of muscle control).
These symptoms cause the patient to fall asleep during routine tasks and interfere with daily life. This may happen quite frequently in a day and without any stimulation. It affects 1 in 2000 people on average and may last from a few years to the entire lifetime of the individual. Unfortunately, a cure is not available yet so it can only be treated at the moment.