Science
Science

Sleepiness vs. Narcolepsy

Written by: Juliann Scholl

Updated March 12, 2021

 

Most people experience extreme fatigue or excessive daytime sleepiness (EDS) from time to time. If this happens to you frequently, you might wonder — "Do I have narcolepsy?"

Being drowsy during the day might not mean that narcolepsy is to blame. Narcolepsy is much less common than EDS and produces symptoms beyond brief incidents of daytime sleep.

What Does Excessive Daytime Sleepiness Look Like?

EDS happens when the body has difficulty regulating its natural sleep-wake schedule (1), resulting in excessive fatigue (2) during the day. EDS can also lead to an uncontrollable urge to sleep, followed by a sleep attack (3) that causes a person to fall asleep for a few seconds or minutes. These attacks can happen at any time, making them dangerous if the sufferer is driving a car.

EDS affects up to 18% of adults (4). Some people with anxiety or depression also report daytime drowsiness. Frequent EDS without a known cause might indicate a sleep disorder.

What Does Narcolepsy Look Like?

Narcolepsy is a condition of the nervous system that affects about one in 2,000 Americans. It affects women and men about equally, and symptoms usually start between 15 and 30 years of age .

Narcolepsy disrupts a person's sleep-wake functions, causing extreme daytime drowsiness and sleep attacks, which are brief episodes of falling asleep. Most people with narcolepsy have difficulty sleeping at night despite being tired during the day.

Some people with narcolepsy have low amounts of hypocretin (5), a neurotransmitter that helps the body stay awake. The causes of other narcolepsy cases are unknown. Factors like genetics, environment, stroke, tumor, upper airway infections, or autoimmune conditions might play a part.

How Can You Tell the Difference?

People with narcolepsy typically suffer from EDS, but individuals experiencing extreme fatigue do not necessarily have narcolepsy. Extreme sleepiness is narcolepsy's predominant symptom.

In addition to EDS, some people with narcolepsy suffer cataplexy, which affects about one out of five patients. Cataplexy is the inability to control the muscles during attacks that can last up to two minutes. During a cataplexy attack, the person's head or jaw might drop, and the knees buckle. All of this happens while the person is awake. Laughter, anger, or other intense emotions can trigger cataplexy.

Sleep paralysis is another common symptom, affecting about a quarter of people with narcolepsy. During sleep paralysis, a person tries to move, but they can't. Paralysis happens after falling asleep or upon waking up and can last up to 15 minutes. Also, one-third of individuals with narcolepsy experience hallucinations (6), either as they wake up (hypnopompic) or fall asleep (hypnagogic).

How is Narcolepsy Diagnosed?

To diagnose narcolepsy, a doctor typically examines a patient's medical and family history, does a physical examination, and conducts tests. Before diagnosing, the doctor might rule out nervous system conditions or other sleep-related disorders (7), such as restless legs syndrome, insomnia, or sleep apnea.

A doctor might recommend that the patient participates in an overnight sleep study that monitors the patient's overnight sleep patterns, including REM sleep movements. A sleep study also collects information about activities while awake, daytime naps, and sleep disturbances. The study might also include spinal fluid collection to measure hypocretin levels.

A doctor might diagnose a patient with one of two types of narcolepsy. Type 1 includes low hypocretin levels, EDS, and cataplexy. People with Type 2 experience EDS without cataplexy and have average amounts of hypocretin.

What Are Possible Underlying Causes of Excessive Sleepiness?

EDS may be due to narcolepsy, but it can also be caused by other underlying conditions (8). Diabetes, sodium fluctuations, excess calcium in the blood, hypothyroidism, sleep apnea, chronic pain, or insomnia could be to blame.

Jet lag, shift work, and insufficient sleep can also trigger EDS. Medications like sleeping pills, tranquilizers, some pain killers, antihistamines, and certain psychiatric drugs can trigger EDS. A mental health issue can also be an underlying factor — EDS and insomnia affect about 80% of people with depression.

What are Tips for Someone Dealing with Daytime Sleepiness or Narcolepsy?

People who struggle with EDS or mild narcolepsy can benefit from improving their sleep hygiene by scheduling daytime naps and maintaining a consistent sleep schedule every day. Keeping the bedroom dark and cool, avoiding caffeine and alcohol in the evening, relaxing, and exercising can also help.

Although there is currently no cure for narcolepsy, there are effective treatment options. Stimulants like modafinil (9) can treat daytime sleepiness, while patients who suffer from cataplexy might take sodium oxybate (10). A sedative can aid sleep at night, and a doctor can prescribe antidepressants to reduce hallucinations, sleep paralysis, and cataplexy. As with all sleep disorders, patients with narcolepsy should work closely with their doctor to find the best treatment.

Final Thoughts

Excessive sleepiness is not always a sign of narcolepsy. Knowing the difference between the two can help you understand how to cope with daytime fatigue. Although there is currently no cure for narcolepsy, medicinal treatment and behavioral changes can help patients reduce their symptoms and maintain active lives.

 

References

 

  1. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Narcolepsy-Fact-Sheet. Accessed on March 10, 2021.
  2. https://www.merckmanuals.com/home/brain,-spinal-cord,-and-nerve-disorders/sleep-disorders/insomnia-and-excessive-daytime-sleepiness-eds Accessed on March 10, 2021.
  3. https://medlineplus.gov/ency/article/000802.htm Accessed on March 10,2021.
  4. https://pubmed.ncbi.nlm.nih.gov/23205286/ Accessed on March 10, 2021.
  5. https://www.nhlbi.nih.gov/health-topics/narcolepsy Accessed on March 10, 2021.
  6. https://pubmed.ncbi.nlm.nih.gov/21637632/ Accessed on March 10, 2021.
  7. https://www.nhlbi.nih.gov/health-topics/sleep-studies. Accessed on March 10, 2021.
  8. https://medlineplus.gov/ency/article/003208.htm Accessed on March 10, 2021.
  9. https://medlineplus.gov/druginfo/meds/a602016.html Accessed on March 10, 2021.
  10. https://medlineplus.gov/druginfo/meds/a605032.html Accessed on March 10, 2021.