What is REM sleep behavior disorder?

This is a condition in which a person acts out their dreams. This can involve sudden movements and outbursts of talking or yelling during sleep. In some cases, it can lead to injury.

Each night, the body goes through 2 different types of sleep. These are called "rapid eye movement" ("REM") sleep and "non-REM" sleep. REM sleep is when most dreaming happens. In people with REM sleep behavior disorder, the body does not stay still the way it normally does during REM sleep.

REM sleep behavior disorder is different from sleepwalking, which is when a person walks or talks in their sleep. Sleepwalking is more common in children than adults, and most people grow out of it. People with REM sleep behavior disorder usually start having symptoms when they are older, often in their 60s or 70s. The disorder starts gradually and gets worse over time. It is often related to other medical conditions.

What are the symptoms of REM sleep behavior disorder?

The main symptom is acting out your dreams. For example, if you dream you are in a fight, you might actually make punching or kicking motions in your bed. Most of these episodes last for less than a minute. You might also talk or yell in your sleep. Very active episodes might wake you up, but you might sleep through milder ones.

People with REM sleep behavior disorder tend to have the most symptoms during the second half of the night. That's because the body goes through more REM sleep during that time. The dreams people act out are often scary or unpleasant. Acting out your dreams can cause injury, for example, if you fall out of bed or hit something. It can also be dangerous for your partner if you make rough or violent movements.

What causes REM sleep behavior disorder?

REM sleep behavior disorder is caused by changes in the brain. These changes can be related to:

• Parkinson disease – This is a brain disorder that affects movement, learning, and memory.

• Dementia with Lewy bodies – This is a brain disorder that causes memory problems.

• Multiple system atrophy – This is a brain disorder that affects movement, balance, and nerves.

• Other medical conditions that affect the brain, such as a stroke or tumor

• Narcolepsy – This is a sleep disorder that makes you feel sleepy all the time and fall asleep suddenly.

• Certain medicines, such as those used to treat depression

For people who do end up having Parkinson disease or another brain disorder, it can take months or years to show other symptoms. If your doctor thinks you are at risk for one of these disorders, they will talk to you about what it means. In many cases, there are treatments that can help.

Should I see a doctor or nurse?

Yes. If you or your partner notice you are acting out your dreams, see your doctor or nurse. They will ask about your sleep episodes as well as any other symptoms you have.

Will I need tests?

Yes. If your doctor or nurse suspects you have REM sleep behavior disorder, they will send you for a "sleep study." For this test, you spend the night in a sleep lab at a hospital or doctor's office. You are hooked up to different machines that monitor your heart rate, breathing, and other body functions. The results of the test can tell your doctor or nurse if you have REM sleep behavior disorder or another sleep disorder.

How is REM sleep behavior disorder treated?

If you have frequent, bothersome, or dangerous episodes during sleep, your doctor might suggest you take medicine. Medicines used to treat REM sleep behavior disorder include:

• Melatonin – This is a hormone that is naturally made by a gland in the brain. Taking melatonin at bedtime can help your body stay still during REM sleep. You can buy melatonin pills in a store or pharmacy without a prescription. But it's important to work with your doctor to figure out the right dose. This might involve starting at a low dose and then increasing it slowly until your symptoms improve.

• Clonazepam (brand name: Klonopin) – This is a medicine used to treat anxiety. It can help treat REM sleep behavior disorder in some cases. Most doctors prefer to try melatonin first, since it has fewer side effects.

If your doctor thinks an antidepressant medicine is causing your sleep symptoms, stopping or switching the medicine can fix the problem.

What can I do on my own?

To help protect yourself and your partner, you should:

• Move any breakable items, such as lamps, away from your bed.

• Make sure any weapons, like guns, are stored safely away from where you sleep.

If you have frequent violent episodes, it might be safest for you and your partner to sleep separately. If you often fall or jump out of bed, you might try using a sleeping bag on the floor or a padded bed rail.