Narcolepsy
What is narcolepsy?
Narcolepsy is a chronic sleep disorder characterized by overwhelming daytime sleepiness and sudden attacks of sleep.
People with narcolepsy often find it difficult to stay awake for long periods of time, regardless of the circumstances. Narcolepsy can cause serious disruptions in your personal and professional lives. Although there’s no cure for narcolepsy, medications and lifestyle changes can help you manage the symptoms.
What causes narcolepsy?
The cause in the vast majority of cases has been found to be a specific problem with the chemical “neurotransmitters” that regulate communications between different groups of nerve cells in the brain. Brain cells in the lateral hypothalamus that produce a neurotransmitter called hypocretin or orexin are lost.
Narcolepsy is hereditary such that some individuals appear genetically predisposed to develop it.
What are the symptoms of narcolepsy?
Excessive daytime sleepiness. The primary characteristic of narcolepsy is overwhelming drowsiness and an uncontrollable need to sleep during the day. People with narcolepsy fall asleep without warning, anywhere and at any time. For example, you may suddenly nod off while at work or talking with friends. You may sleep for just a few minutes or up to a half-hour before awakening and feeling refreshed, but then you fall asleep again.
Cataplexy. This condition can cause a range of physical changes, from slurred speech to complete weakness of most muscles, and may last for a few seconds to a few minutes. Cataplexy is uncontrollable and is often triggered by intense emotions, usually positive ones such as such as laughter or excitement, but sometimes fear, surprise or anger. For example, your head may droop uncontrollably or your knees may suddenly buckle when you laugh.
Sleep paralysis. People with narcolepsy often experience a temporary inability to move or speak while falling asleep or upon waking. These episodes are usually brief — usually lasting only several seconds to several minutes — but they can be frightening. You may be aware of the condition and have no difficulty recalling it afterward, even if you had no control over what was happening to you.
Hallucinations. These hallucinations, called hypnagogic hallucinations, may take place when a person with narcolepsy falls quickly into REM sleep, as they do at sleep onset at night and periodically during the day. Because you may be semiawake when you begin dreaming, you experience your dreams as reality, and they may be particularly vivid and frightening.
How is narcolepsy diagnosed?
Formal diagnosis may require an overnight sleep study (polysomnogram) followed by a daytime Multiple Sleep Latency Test (MSLT). The MSLT measures how long it takes for you to fall asleep during the day. You will be given up to five ‘nap’ opportunities scheduled 2 hours apart. People who have narcolepsy fall asleep easily and enter into rapid eye movement (REM) sleep quickly.
How is narcolepsy treated?
Narcolepsy has no cure, but medications and lifestyle modifications can help you manage the symptoms. Medications Medications that can be helpful include stimulants and wakefulness promoting agents, sodium oxybate (Xyrem) which is ingested at night. All have their own advantages and potential side effects and must be selected carefully for each individual patient.