Narcolepsy is condition characterized by excessive sleepiness associated with temporary muscle weakness, paralysis while sleeping or upon awakening, hallucinations and disrupted sleep. It is often caused by a deficiency in the neurotransmitter hypocretin.
In most cases, the first symptom experienced appears to be excessive and overwhelming sleepiness. The other symptoms may begin alone or in combination months or years after the onset of daytime sleep attacks.
With narcolepsy, an individual is likely to become drowsy or to fall asleep, often at inappropriate times and places. Attacks of drowsiness may be irresistible and vary in frequency from a few incidents to multiple occurrences in a single day and can persist for only a few minutes or last for hours.
Although not always present, the most dramatic symptom of narcolepsy is cataplexy – a sudden onset of muscle weakness, ranging from mild to complete paralysis. Cataplexy attacks are usually triggered by laughter or anger.
Sleep paralysis is characterized by a feeling of complete paralysis when falling asleep or awakening. This paralysis is often associated with hypnogogic (when going to sleep) or hypnopompic (upon awakening) hallucinations. These hallucinations can also occur independently of paralysis.
Narcolepsy is often mistaken for depression, epilepsy or the side-effects of medication. Symptoms are usually first noticed in teenagers or young adults, though it can occur in men or women of any age.
Symptoms are usually first noticed in teenagers or young adults, although it can occur in men or women of any age. Narcolepsy is often misdiagnosed or not diagnosed at all. The sleepiness may be mistaken for low motivation, laziness, or depression. Attention deficits may lead to a mistaken diagnosis of a learning disability. The hallucinations may be mistaken for psychosis or epilepsy.
The symptoms of narcolepsy, especially the excessive daytime sleepiness and cataplexy, often become severe enough to cause serious disruptions in a person’s social, personal and professional lives and severely limit activities. Accidental injury is not uncommon.
Diagnosis can be made with the help of several tests performed by sleep specialists at the Sleep Medicine Center, including the polysomnogram or sleep study and the multiple sleep latency test.
Polysomnogram is performed to measure the quality of sleep and to assess for abnormalities which may disrupt sleep. In this test, the patient sleeps in the sleep center at his or her normal bedtime while electrodes and other sensors are used to monitor brain waves, eye movements, respiration and movement, EKG and leg movement. A variety of other systems can be monitored as requested by the patient’s referring physician.
The multiple sleep latency test measures the degree of daytime sleepiness and also detects how soon the rapid eye movement (REM) phase of sleep begins. The patient is given the opportunity to sleep every two hours during a normal wake period. The multiple sleep latency test is typically performed after an all-night polysomnogram and four or five naps are obtained.
Once a diagnosis of narcolepsy is established, effective treatment is available. General treatment options will be discussed by the physician at the initial office visit, and individual treatment plans formulated when the test results are available.
If you are experiencing symptoms of excessively and overwhelming sleepiness during the day, even after you have had a full night’s sleep or if you fall asleep at inappropriate times, you should consult a physician.