Narcolepsy affects an estimated 250,000 Americans. People with narcolepsy have frequent "sleep attacks" at various times of the day, even if they have had a normal amount of night-time sleep. These attacks last from several seconds to more than 30 minutes. People with narcolepsy also may experience cataplexy (loss of muscle control during emotional situations), hallucinations, temporary paralysis when they awaken, and disrupted night-time sleep. These symptoms seem to be features of REM sleep that appear during waking, which suggests that narcolepsy is a disorder of sleep regulation. The symptoms of narcolepsy typically appear during adolescence, though it often takes years to obtain a correct diagnosis. The disorder (or at least a predisposition to it) is usually hereditary, but it occasionally is linked to brain damage from a head injury or neurological disease.
Once narcolepsy is diagnosed, stimulants, antidepressants, or other drugs can help control the symptoms and prevent the embarrassing and dangerous effects of falling asleep at improper times. Naps at certain times of the day also may reduce the excessive daytime sleepiness.
In 1999, a research team working with canine models identified a gene that causes narcolepsy–a breakthrough that brings a cure for this disabling condition within reach. The gene, hypocretin receptor 2, codes for a protein that allows brain cells to receive instructions from other cells. The defective versions of the gene encode proteins that cannot recognize these messages, perhaps cutting the cells off from messages that promote wakefulness. The researchers know that the same gene exists in humans, and they are currently searching for defective versions in people with narcolepsy.
Overview of Narcolepsy:
Symptoms:
Excessive daytime sleepiness (EDS), involuntary sleeping attacks during the day, and frequent awakenings during the night. Also cataplexy (sudden loss of voluntary muscle control), hallucinations, and paralysis during sleep onset or awakening are seen.
Diagnosis:
A careful history and physical exam by your sleep specialist. A polysomnogram (PSG) and a multiple sleep latency test (MSLT) are also needed to confirm this diagnosis.
Treatment:
There is no cure for narcolepsy. However, there are medications available to counteract some of the associated symptoms. For example, EDS can be treated with amphetamines. However, patients must be closely monitored because of the potentially serious side effects. Patients who experience cataplexy can be treated with some antidepressants. Patients can also modify behavior by establishing regular sleeping patterns, avoiding alcohol and caffeinated products several hours before bedtime, and participating in relaxing activities prior to bedtime.
