Hypersomnia vs. Narcolepsy: Similarities and Differences

Hypersomnia and narcolepsy are closely linked and often confused with one another. However, there are distinct differences.

Narcolepsy and Hypersomnia Affect REM Sleep Differently

Rapid eye movement (REM) sleep is one of the main stages of sleep. It usually starts about 90 minutes after you fall asleep and occurs multiple times a night. During REM sleep, you experience eye movements, twitching, and most of your dreams.

With narcolepsy, REM sleep occurs within 15 minutes after you drift off. People with hypersomnia usually don’t experience this change in the typical REM sleep cycle, which may account for some of the differences in symptoms between the conditions.

Treatment Approaches Can Differ

Healthcare providers may treat narcolepsy and hypersomnia differently.

Stimulant medications like Adderall (amphetamine), Ritalin (methylphenidate), and Provigil (modafinil) are common treatments for narcolepsy. These options may be less effective for hypersomnia.

Healthcare providers may prescribe medications to address cataplexy and sleep paralysis in narcolepsy. These medications include Xyrem (sodium oxybate), Wakix (pitolisant), and certain antidepressants. They may be less effective for hypersomnia.

If you have cataplexy, it’s also important to follow your healthcare provider’s safety precautions around things such as driving.

Narcolepsy and Hypersomnia May Have Different Causes

Experts are still learning the causes of both sleep disorders. They do know that people with type 1 narcolepsy (narcolepsy with cataplexy) have lower levels of hypocretin, a brain chemical that helps regulate your waking state and REM sleep. People with type 2 narcolepsy or hypersomnia don’t have this difference.

“Hypersomnia” often refers to idiopathic hypersomnia. You can also develop medication or substance-use hypersomnia, which may happen from the use of these drugs:

• Hypnotic medications, such as Ambien (zolpidem), Halcion (triazolam), and others
• Antihistamines such as Benadryl (diphenhydramine) and Zyrtec (cetirizine)
• Anticholinergic drugs, such as Atropen (atropine), hyoscine (scopolamine), and others
• Opiates such as Vicodin (hydrocodone) and Oxycodone (oxycontin)
• Blood pressure medications
• Antiepileptic (antiseizure) medications such as Carbatrol (carbamazepine) and Valproic (valproate) 
• Cannabis, alcohol, and other recreational drugs

Hypersomnnia and Narcolepsy Impact the Sexes Differently

Research suggests that idiopathic hypersomnia is more common among women than men. This isn’t the case with narcolepsy, which affects the sexes more equally.

However, researchers found women with narcolepsy are less likely to report symptoms, delaying diagnosis and treatment. Compared to men, women may experience a less significant impact on their lifestyle and relationships.

Beyond sharing some symptoms, hypersomnia and narcolepsy have several similarities, including in diagnosis and management.

Hypersomnia and Narcolepsy May Begin at Similar Ages

The first symptoms of both hypersomnia and narcolepsy typically occur before age 30. Narcolepsy often begins to appear at ages 10-25. For idiopathic hypersomnia, the age of onset is also in adolescence or young adulthood.

Hypersomnia and Narcolepsy Both Have a Genetic Component

Both conditions have a genetic component. Research suggests that about a third of people with idiopathic hypersomnia have a family history of hypersomnia, narcolepsy, or another sleep disorder.

For narcolepsy, there isn’t as clear a pattern of inheritance, but having parents or siblings with the condition raises your risk by about 40 times.

The Same Diagnostic Tests Detect Hypersomnia and Narcolepsy

Healthcare providers may use the same tests to diagnose hypersomnia and narcolepsy. These include:

• Physical examination and a review of symptoms and medical history
• Blood tests to detect other potential causes of symptoms, such as seizures or sleep apnea
• A multiple sleep latency test, which measures how quickly you fall asleep
• Polysomnography (a sleep study), which measures your brain activity, breathing, heart rate, level of oxygen, and more
• Mental health evaluation for depression or other conditions 
• An electrocardiogram (ECG), which measures your heart activity
• An electroencephalogram (EEG), which measures your brain activity

Lifestyle Changes Help Manage Both Conditions

Along with medications, lifestyle changes are important for managing both hypersomnia and narcolepsy. These strategies include:

• Go to bed and get up at the same time every day
• Aim for 7-8 hours of sleep per night
• Ensure your bedroom is comfortable, quiet, and dark
• Before bedtime, avoid alcohol, caffeine, or medications that affect your symptoms
• Stop or avoid smoking
• Relieve stress with relaxing activities, such as walking, light exercise, or breathing exercises
• Get regular exercise, aiming for 150 minutes per week

You can have both conditions at the same time: Narcolepsy, a chronic condition, can trigger episodes of hypersomnia.

The best way to tell which condition you have is to look at the symptoms. Sleep attacks and cataplexy are signs of narcolepsy, but not hypersomnia. In contrast, daytime naps aren’t usually refreshing with idiopathic hypersomnia, but they are with narcolepsy.

If you have both conditions, IH can make it harder for healthcare providers to detect narcolepsy.

If you have or believe you have a sleep disorder like narcolepsy or idiopathic hypersomnia, it’s important to know when to seek care. Signs to call a healthcare provider include:

• You have symptoms of narcolepsy, especially sleep attacks and cataplexy
• You have repeated episodes of excessive daytime sleepiness, which impact your function at school or work
• Treatments aren’t improving your symptoms
• Your symptoms get worse
• You experience new symptoms

Several medical specialists may treat narcolepsy or IH. When seeking care, a primary care provider may refer you to a neurologist, sleep specialist, psychiatrist, or psychologist.

Hypersomnia and narcolepsy are both sleep disorders that cause excessive daytime sleepiness.

Hypersomnia makes it hard to wake up from long sleep periods, and daytime naps aren’t refreshing. Narcolepsy causes sleep attacks, cataplexy, and sleep paralysis.

The two conditions share some treatment options, with lifestyle changes playing a role in managing both conditions.