Rare: 20,000-200,000 cases a year in the USA
What happens in the brain
Here shows the hypocretin in a normal brain compared to the much lower levels in a brain of someone with narcolepsy.
Those who suffer from narcolepsy constantly fall asleep during the day.
The disorder begins between the ages of 10-20 and stays for life. The first symptoms are usually excessive sleepiness during the day, and over time other symptoms develop.
Those who suffer feel the same amount of sleepiness throughout the day that a normal person would feel if they went without sleep for 48-72 hours straight. Furthermore, at night narcoleptics wake up frequently, suffer from vivid nightmares, and sleep paralysis.
The brain tries to counteract the desire for sleep with the desire for lots of fatty foods, so narcolepsy often has the side effect of obesity. Another common disorder that occurs with narcolepsy is catoplexy, which affects 70% of those with narcolepsy.
Diagnosis and Prognosis
Only about 20-25% of narcoleptics experience all the symptoms.
Symptoms usually get worse for the first 2-3 decades before getting a little better.