What narcolepsy and hypersomnias are
Hypersomnia is the umbrella term for excessive daytime sleepiness not explained by lack of sleep hours. Narcolepsy is the best known: a chronic neurological disorder in which the brain poorly regulates the boundary between wakefulness and sleep.
In type 1 narcolepsy there is a loss of the neurons that produce hypocretin (orexin), a substance that keeps wakefulness stable. That loss explains the characteristic symptoms, including cataplexy.
There are other causes of excessive sleepiness — idiopathic hypersomnia, insufficient sleep syndrome, sleep apnea, circadian rhythm disorders, medication effects. Telling them apart is the first goal of the assessment, because the treatment is completely different.
Characteristic symptoms
- Excessive daytime sleepiness, every day, not improved by more hours in bed
- Irresistible sleep attacks, sometimes in inappropriate situations
- Cataplexy: sudden, brief loss of muscle tone triggered by strong emotion — laughter, surprise, anger — with consciousness preserved
- Sleep paralysis: temporary inability to move when falling asleep or waking
- Vivid hallucinations in the transition between wakefulness and sleep
- Fragmented night-time sleep, with several awakenings
- Automatic behaviours: carrying on a task with no memory of it afterwards
The impact on daily life
Chronic sleepiness affects school and work performance, relationships and safety. The risk of road and workplace accidents is significantly higher, and driving requires specific clinical assessment.
There is also the weight of not being taken seriously. Many people with narcolepsy spend years being told they sleep too little, go to bed too late or are depressed, before reaching a diagnosis.
How it is diagnosed
Assessment starts with a detailed clinical history and sleepiness scales, such as the Epworth Sleepiness Scale, complemented by a sleep diary and, when useful, actigraphy over one to two weeks.
The next step is to rule out the more frequent causes of sleepiness — first and foremost sleep apnea and insufficient sleep. A sleep study is usually required.
Confirming narcolepsy requires specific tests, namely the multiple sleep latency test (MSLT), performed in a laboratory the day after polysomnography. These tests are arranged with partner centres whenever indicated.
Treatment options
Scheduled naps
Short, planned naps through the day consistently reduce sleepiness and sleep attacks. It is one of the most effective measures and remains useful even alongside medication.
Routine and sleep hygiene
Fixed schedules, sufficient night-time sleep, regular exercise and caffeine management create the base on which any other treatment works better.
Medication for sleepiness
There are effective wake-promoting drugs, chosen according to each person's profile, symptom intensity and other health conditions.
Treatment of cataplexy
Cataplexy responds to specific treatment, different from that used for sleepiness. Controlling these episodes has an enormous impact on autonomy and safety.
Follow-up and accommodations
Narcolepsy is chronic, but well managed it allows a full life. We also help with liaison with school or employer and with assessing fitness to drive.
When to seek help
Seek assessment if you feel sleepy almost every day despite sleeping enough, if you have fallen asleep in situations where you should not have, or if you have had episodes of sudden muscle weakness linked to emotions.
If you have fallen asleep while driving, the assessment is urgent.
Frequently asked questions
No — on the contrary, it rarely is. The most frequent causes of daytime sleepiness are insufficient sleep and sleep apnea. That is why assessment always starts by ruling those out.
There is no cure, but there is effective treatment. With the right combination of behavioural measures and medication, most people control symptoms well and maintain a normal professional and personal life.
It depends on symptom control and requires individual clinical assessment. With effective treatment and controlled sleepiness, many people retain fitness to drive. It is a matter to discuss in consultation, never to decide alone.
Educational information reviewed by our clinical team. It does not replace an individual medical consultation.