Narcolepsy is a sleep-wake disorder that usually develops during adolescence and early adulthood. If you develop this condition later in life, it’s known as late-onset narcolepsy.

Narcolepsy is a common disorder of the sleep-wake cycle. It affects the rapid eye movement (REM) sleep stage, creating unusual sleep cycles.

Narcolepsy symptoms persist throughout the day and may impair your daily activities. Living with this condition can mean you experience excessive daytime sleepiness.

You may fall asleep without realizing it or feel an overwhelming urge to nap regularly. Many people living with narcolepsy also experience muscle weakness (cataplexy), sleep paralysis, or hallucinations.

Keep reading to learn more about the onset of narcolepsy.

Yes. You can develop narcolepsy at any age. However, it is less common after the age of 50 years.

Narcolepsy typically develops between early childhood and 50 years, but most people are diagnosed before age 30.

Narcolepsy after the age of 50 years is not common, but it does happen.

Like many medical conditions, patterns can be seen in the onset of narcolepsy. There appear to be two peak diagnostic ages, one around age 15 years and a second at age 35 years.

When narcolepsy develops around or after the peak age of 35 years, it’s known as late-onset narcolepsy.

In general, the underlying causes of narcolepsy — at any age — are not well understood. It’s thought to be a disorder related to:

  • genetics
  • autoimmunity
  • hypocretin deficiency
  • neurotransmitter imbalances
  • changes to the brain’s structure (very rarely, lesions in the part of the brain called the hypothalamus)

What does the research say?

Because late-onset narcolepsy is less common than early-onset narcolepsy, research is limited. Currently, the research seems to show no clear cause but does seem to indicate that late-onset symptoms may be more severe.

A 2020 case study of narcolepsy in a 69-year-old man found no possible triggers to explain the disorder’s onset. Researchers noted his symptoms rapidly increased in severity, but no important neurological, physical, or cognitive changes were found.

There were no distinguishing features between his late-onset narcolepsy and cases of early-onset narcolepsy.

A 2021 case report and brief literature review had similar findings. Narcolepsy developed in a 58-year-old male. No factors differentiating early- and late-onset narcolepsy were revealed on examination or through testing.

A small 2023 study of 101 people found that late-onset narcolepsy was associated with greater symptom severity — to the point that study authors suggest it may be a unique subtype of the disorder. The data defined late-onset narcolepsy as cases past the age of 15 years, a much younger classification compared with other research.

Increased symptom severity was noted in a much larger narcolepsy study in 2020. Researchers compared early- and late-onset narcolepsy in more than 800 people and found that late-onset narcolepsy was associated with greater symptom severity.

The study’s authors also found more genetic risk factors in the early-onset group.

While there may not yet be a known trigger or cause that’s specific to late-onset narcolepsy, symptom severity does appear to differ from early-onset development.

Overall, the limited research reveals no major differences between the pathology of early- and late-onset narcolepsy, but symptoms may be more severe if you develop this condition later in life.

What should I do if I think I have narcolepsy?

Knowing when you’re living with narcolepsy can be tricky.

Sleep-wake disorders are often associated with nighttime alertness. If you feel as though you’re getting a full night’s sleep, a sleep-wake disorder probably isn’t the first thing on your mind.

Regular excessive daytime sleepiness (EDS) is not a typical part of life, however. EDS is often the most obvious symptom of narcolepsy and is a good reason to speak with your primary doctor.

Once other neurological causes and physical conditions have been ruled out, your doctor can refer you to a sleep clinic for specialized sleep studies.

There is no cure for narcolepsy. It’s a lifelong condition, but it isn’t considered progressive. This means it won’t worsen as you age.

Plus, treatment can help manage symptoms. Symptom severity can vary over the course of a lifetime with narcolepsy, but cataplexy is the symptom most likely to improve with age.

Narcolepsy can occur at any age, but most people develop this condition in their mid-teens and early adulthood. When narcolepsy begins around or after age 35 years, it’s known as late-onset narcolepsy.

Currently, limited research exists on narcolepsy that develops later in life. The data that does exist has not found any clear pathological difference between early- and late-onset narcolepsy, though evidence suggests late-onset narcolepsy may be linked to more severe symptoms.