A physical exam and exhaustive medical history are essential for proper diagnosis of narcolepsy. However, none of the major symptoms is exclusive to narcolepsy. Several specialized tests, which can be performed in a sleep disorders clinic or sleep lab, usually are required before a diagnosis can be established. Two tests that are considered essential in confirming a diagnosis of narcolepsy are the polysomnogram (PSG) and the multiple sleep latency test (MSLT).
The PSG is an overnight test that takes continuous multiple measurements while a patient is asleep to document abnormalities in the sleep cycle. A PSG can help reveal whether REM sleep occurs at abnormal times in the sleep cycle and can eliminate the possibility that an individual’s symptoms result from another condition.
The MSLT is performed during the day to measure a person’s tendency to fall asleep and to determine whether isolated elements of REM sleep intrude at inappropriate times during the waking hours. As part of the test, an individual is asked to take four or five short naps usually scheduled two hours apart.
Although there is no cure for narcolepsy, the most disabling symptoms of the disorder (EDS and symptoms of abnormal REM sleep, such as cataplexy) can be controlled in most people with drug treatment. Sleepiness is treated with amphetamine-like stimulants, while the symptoms of abnormal REM sleep are treated with antidepressant drugs.
There has recently been a new medication approved for those who suffer from narcolepsy with cataplexy. This drug, called Xyrem, helps people with narcolepsy get a better night’s sleep, allowing them to be less sleepy during the day. Patients with narcolepsy can be substantially helped — but not cured — by medical treatment.
Lifestyle adjustments such as avoiding caffeine, alcohol, nicotine, and heavy meals, regulating sleep schedules, scheduling daytime naps (10-15 minutes in length), and establishing a normal exercise and meal schedule may also help to reduce symptoms.