Some people with narcolepsy may be able to drive safely, especially if they drive when well-rested and stick to short trips.

Most people with narcolepsy can legally drive in the United States. However, it may not always be safe to do so. Regulations may vary from state to state.

Most states rely on a voluntary process to determine whether a person is medically able to drive. Some states allow medical professionals or family members to contact the state department of motor vehicles with concerns.

The Federal Motor Carrier Safety Administration recommends disqualifying individuals with a narcolepsy diagnosis, regardless of treatment.

According to 2022 statistics, narcolepsy may put you at a higher risk of motor vehicle collisions than people without narcolepsy.

A 2019 study of more than 1,300 people in Taiwan suggested that the risk of hospitalization for motor vehicle accident injuries was much higher in participants with narcolepsy than in those who did not have a narcolepsy diagnosis.

In one 2020 study, people with narcolepsy reported more sleep-related collisions than people with other sleep disorders.

This study also found that individuals with narcolepsy were three to four times more likely to report an accident due to sleepiness than somebody in the general population.

Excessive drowsiness may also lead to inattention or to falling asleep behind the wheel.

In the same 2020 study, researchers found that:

  • 66% of participants with narcolepsy reported falling asleep while driving
  • 29% experienced cataplexy while driving
  • 12% experienced sleep paralysis while driving

Cataplexy is characterized by a sudden limpness or weakness of your muscles. Cataplexy can cause mild symptoms, such as eyelid drooping, but can also cause complete loss of bodily control.

Sleep paralysis is when you’re temporarily unable to move when waking or falling asleep.

Medications can help reduce sleepiness in people with narcolepsy. But even with medication, people with narcolepsy rarely have the same ability to stay awake as people in the general population.

There’s been little research examining how medications affect driving performance.

One small 2019 study examined participants with narcolepsy — or another sleep disorder called idiopathic hypersomnia — during real and simulated driving tests.

Participants treated with 400 milligrams of modafinil had better results during their simulated driving performances than participants treated with a placebo.

Caffeine may also be beneficial for improving driving performance in people with narcolepsy.

A 2020 review of 45 studies found evidence that, in the general population, caffeine improves scores on tests of:

  • reaction time
  • attention
  • executive function
  • vehicle control

In a small 2020 study, researchers found that 200 milligrams of caffeine taken daily for a week reduced drowsiness and increased alertness in 16 people with narcolepsy. However, larger studies are needed to confirm these results.

If you have narcolepsy and plan on driving, you can minimize your chances of having an accident by taking a 15- to 20-minute nap before driving. Research from 2020 suggests that naps of this length improve driving performance, but longer naps can cause grogginess.

Other ways to minimize your risk of motor vehicle accidents, according to this 2020 study, include:

  • avoiding driving when you’re particularly sleepy, like late at night or early morning
  • keeping trips short
  • taking nap breaks during long drives
  • taking turns driving with another person
  • avoiding driving after meals, or after consuming simple sugars or alcohol

One 2020 study suggested that people who are drowsy can’t reliably self-rate their impairment.

Some signs of impairment include:

  • an inability to focus
  • frequent yawning or trouble keeping your eyes open
  • nodding off or finding your head falling
  • missing road signs
  • not remembering the last few miles of driving
  • drooping eyelids
  • frequent daydreaming
  • trouble maintaining speed
  • drifting out of your lane

It can be difficult to know if it’s safe for you to drive. The study linked above notes that there are no standard guidelines for people with narcolepsy.

However, if you answer yes to most of the following questions, it may be time to reassess whether you should be on the roads:

  • Do your friends and family think it’s unsafe for you to drive?
  • Have you fallen asleep at the wheel before?
  • Is your narcolepsy poorly controlled?
  • Have you gotten into, or almost gotten into, a collision that was related to drowsiness?
  • Have you experienced cataplexy or sleep paralysis while driving?

Your doctor can help you determine whether it’s safe for you to drive. They can assess your ability to stay awake during monotonous tasks.

Safe driving tips for people with narcolepsy

If you absolutely must drive, you can minimize your chances of an accident by:

  • avoiding sources of distraction (such as listening to music, talking with passengers, or using a cell phone)
  • avoiding driving after taking medications that can cause daytime sleepiness (such as antihistamines)
  • avoiding driving after eating or drinking alcohol
  • avoiding driving more than 30 to 60 minutes in a row
  • avoiding long drives and heavy traffic
  • taking naps before driving
  • pulling over if you find yourself getting sleepy while driving

If you have narcolepsy but are not cleared to drive, you can talk with your doctor about medications that may better manage your narcolepsy symptoms. If your symptoms improve on different medication, you driving ability can be reassessed.

Moreover, the Americans with Disabilities Act requires that employers provide reasonable accommodations for individuals with narcolepsy.

This could mean adjusting work hours to be more flexible if you rely on public transportation, or allowing you to work from home.

If you have treated narcolepsy, you are legally able to drive in the United States. But it may not always be safe to drive. People with narcolepsy are at a heightened risk of motor vehicle accidents.

Your doctor can help you figure out whether it’s safe for you to drive by assessing your ability to stay awake.

You can minimize your chances of getting into an accident by avoiding extended periods of driving and taking frequent naps.