Key takeaways
- Up to 1 in 3 people with narcolepsy also meet the criteria for attention deficit hyperactivity disorder (ADHD). Both disorders may share underlying mechanisms involving neurotransmitters.
- Common overlapping symptoms include excessive daytime sleepiness, difficulty paying attention, impulsivity, and problems with organization and time management. However, sleep attacks and cataplexy are distinct narcolepsy symptoms not typical of ADHD.
- Both conditions may respond to similar medications, including stimulants like modafinil and amphetamines.
At first glance, narcolepsy and attention deficit hyperactivity disorder (ADHD) may not seem to have much in common. We know that narcolepsy causes excessive sleepiness, while ADHD is best-known for hyperactivity.
But research suggests that these two neurological disorders overlap and may even share underlying mechanisms.
It’s not uncommon to have both narcolepsy and ADHD. In fact, studies have found that between 25% and 33% of people with narcolepsy also meet the criteria for ADHD (compared to only
But even if you don’t have both disorders entirely, there’s still some symptom overlap.
ADHD-like symptoms are very common in people with narcolepsy.
For instance, the excessive daytime sleepiness seen in narcolepsy can lead to inattention, problems with executive function, and impulse control problems — all symptoms that mimic ADHD and respond well to stimulant medications.
Similarly, people with ADHD often have sleep-related problems. Research suggests that sleep problems, like excessive daytime sleepiness, are common in people with ADHD across their lifetime, with a higher relative risk in childhood.
Sometimes the symptoms of the two disorders overlap, leading to misdiagnosis.
Narcolepsy and ADHD are two distinct disorders, but some evidence suggests they may share some common mechanisms.
One underlying mechanism may involve the neurotransmitter noradrenaline. Experts believe that ADHD is linked to the dysregulation of the neurotransmitters dopamine and noradrenaline. Research suggests that noradrenaline dysfunction may also lead to changes in REM sleep, similar to what’s observed in narcolepsy.
Both ADHD and narcolepsy are effectively treated with stimulants, which target these specific neurotransmitters.
Another similarity between the two disorders relates to how iron is metabolized in the body.
Some people with ADHD and hypersomnia (excessive daytime sleepiness or prolonged nighttime sleep) meet the diagnostic criteria for type 2 narcolepsy, also called narcolepsy without cataplexy (sudden, brief episodes of muscle weakness triggered by strong emotions).
These individuals lack a specific genetic trait seen in people with type 1 narcolepsy (narcolepsy with cataplexy) as well as those with type 2 narcolepsy without ADHD. This might suggest that people with ADHD and hypersomnia have their own subtype of type 2 narcolepsy.
ADHD and narcolepsy symptoms
Narcolepsy is a sleep disorder characterized by excessive daytime sleepiness occurring alone or with sudden, brief episodes of muscle weakness triggered by strong emotions (cataplexy).
There are two major types of narcolepsy:
- Type 1 narcolepsy (narcolepsy with cataplexy): Type 1 involves low levels of hypocretin (a brain chemical that regulates sleep and wakefulness) or the presence of cataplexy and excessive daytime sleepiness.
- Type 2 narcolepsy (narcolepsy without cataplexy): Type 2 involves excessive daytime sleepiness without cataplexy and with typical hypocretin levels.
ADHD is a neurodevelopmental disorder characterized by difficulty with paying attention, impulsivity, and hyperactivity.
ADHD diagnostic criteria divide people into the following types:
- inattentive
- hyperactive-impulsive
- combined presentation
Some symptoms that may be seen in both narcolepsy and ADHD include:
- excessive daytime sleepiness
- difficulty paying attention or staying focused
- impulsivity or difficulty controlling behavior
- difficulty with organization and time management
- hyperactivity or restlessness
- sleep disturbances, such as difficulty falling asleep or staying asleep
There are also distinct differences between the two disorders. For instance, “sleep attacks” (suddenly falling asleep without warning) and cataplexy are distinct narcolepsy symptoms that are not typical ADHD symptoms.
Several medications are available to treat both narcolepsy and ADHD.
Doctors often prescribe certain stimulants, such as modafinil (Provigil) and armodafinil (Nuvigil), to increase alertness and wakefulness in narcolepsy. Doctors may also prescribe these medications off-label to help manage ADHD symptoms, such as inattention and impulsivity.
The stimulant methylphenidate (Ritalin) is often used to treat ADHD and may be used off-label for narcolepsy to help with daytime sleepiness.
Other medications doctors may use to treat both narcolepsy and ADHD include:
- amphetamines, such as dextroamphetamine (Dexedrine) and lisdexamfetamine (Vyvanse)
- non-stimulant medications, such as atomoxetine (Strattera)
Though they’re distinct disorders, narcolepsy and ADHD have overlapping symptoms and may also share some underlying mechanisms. Both are neurodevelopmental disorders that may feature daytime sleepiness, inattention, and declined executive function.
If you have any symptoms of narcolepsy or ADHD, consider reaching out to a healthcare clinician to get a professional diagnosis. Both disorders are highly treatable, and the right treatment may help you manage your symptoms and improve your quality of life.