The symptoms of narcolepsy vary widely between affected individuals, with some people experiencing frequent symptoms and others finding the condition rarely affects them.
Some of the characteristic symptoms of narcolepsy include:
Excessive daytime sleepiness – This is often the first symptom to appear and is usually the most debilitating. Individuals may feel drowsy throughout the day and most people find it difficult to stay awake.
Sleep attacks – Sleep attacks are another common symptom of narcolepsy. A person will fall asleep suddenly and at inappropriate times such as while eating or driving. The length of time the person is asleep for varies between individuals but often they stay asleep for around 15 minutes before waking up refreshed. These sleep attacks can occur several times a day.
Cataplexy – Cataplexy is a sudden, temporary loss of muscle control during which the mouth may drop open or the head may slump, for example. Other typical signs include the legs giving way, speech being slurred or double vision suddenly occurring. Cataplexy affects around 75% of all people with narcolepsy.
Cataplexy attacks usually occur after extreme emotions such as anger, stress, laughter or surprise. These attacks may last for anything from a few seconds to 30 minutes. Some people experience cataplexy on a daily basis while in others, the attacks only occur once or twice a year. The symptoms of cataplexy can improve with age.
Some other examples of narcolepsy symptoms include:
Night time sleep may be restless and disrupted by vivid nightmares, repeated waking and hot flushes.
Automatic behavior might occur, where a person continues to carry out day time activities such as walking or talking while they are asleep
Hallucinations may occur, with the person seeing and/or hearing things that are not present.
Reviewed by Sally Robertson, BSc