Sleep plays a vital role in our health, and for people with Parkinson’s disease, it becomes even more critical. One lesser-known, but very important, condition linked to both sleep and Parkinson’s is REM Sleep Behavior Disorder, or RBD. That’s why many neurologists routinely ask about sleep—it can be the window into early changes in the brain.

What Exactly Is REM Sleep Behavior Disorder?

Let’s start with the basics. REM (Rapid Eye Movement) is the sleep stage where dreaming occurs. During this phase, the brain typically sends signals to paralyze the muscles, stopping you from physically acting out your dreams.

But in REM Sleep Behavior Disorder, that protective mechanism fails. Instead of lying still, individuals with RBD may move, speak, shout, or even leap out of bed while dreaming—often reacting to vivid or action-filled dreams. This can be startling or even dangerous.

Common signs of RBD include:

• Sudden movements such as punching, kicking, or jumping from bed
• Vocal sounds like shouting, talking, or crying out
• A lack of awareness of these behaviors, making input from a bed partner especially helpful

RBD can be idiopathic (no known cause) or secondary to other factors like medications. For example, antidepressants such as mirtazapine have been shown to trigger RBD in some cases (Onofrj M, 2003).

The Link Between RBD and Parkinson’s Disease

Idiopathic RBD isn’t just a sleep disorder—it can be an early warning sign of neurological conditions. One large study found that 81% of elderly males with idiopathic RBD eventually developed Parkinson’s or related syndromes, with motor symptoms appearing on average 10 years after the initial RBD diagnosis (Jin H et al., 2017).

This makes RBD one of the most powerful early predictors of Parkinson’s, well before tremors or stiffness begin.

How Is RBD Diagnosed?

Diagnosis begins with a detailed history—often including your bed partner’s observations. If your doctor suspects RBD, they may refer you for a polysomnography (sleep study), which monitors your brain waves, muscle activity, and eye movements overnight. Some centers even record video during the study to capture dream-enactment behaviors. While usually done in a sleep clinic, some institutions may offer home-based testing.

What Are the Treatment Options?

Treatment depends on the underlying cause. If medications like mirtazapine or certain antidepressants are suspected triggers, your doctor may suggest changing them first.

When medical treatment is necessary, clonazepam and melatonin are commonly prescribed first-line options (Jiménez-Jiménez FJ, 2021). These medications help reduce the frequency and severity of dream-enactment behaviors. However, they must be used with care, especially in older adults or those with memory or balance issues.

Safety modifications are also essential:

• Lowering the bed height
• Removing sharp or hard objects from the room
• Placing cushions around the bed
• In some cases, sleeping in separate beds until symptoms are controlled

These practical changes can help prevent injury to both the patient and their partner.

What Should You Do if You Suspect RBD?

If you or someone close to you notices unusual movements during sleep, bring it up with your GP or neurologist. While RBD might sound straightforward, only a sleep specialist can confirm the diagnosis and distinguish it from other sleep disorders.

If diagnosed, it may also be worthwhile to see a movement disorder neurologist—a specialist who can monitor for early signs of Parkinson’s and guide future steps, including regular follow-ups.

While acting out dreams may seem like just an odd quirk of sleep, RBD can be a powerful clue into brain health. For some, it’s the first sign that something deeper may be going on. With early recognition and management, individuals can stay safer at night—and potentially catch neurological changes early, long before other symptoms appear.

References:

• Mayo Clinic. (2018). REM Sleep Behavior Disorder.
• Jin H, Zhang JR, Shen Y, Liu CF. (2017). Clinical significance of REM sleep behavior disorders and other non-motor symptoms of parkinsonism. Neurosci Bull, 33(5):576–584. doi: 10.1007/s12264-017-0164-8.
• Jiménez-Jiménez FJ, Alonso-Navarro H, García-Martín E, Agúndez JAG. (2021). Current Treatment Options for REM Sleep Behaviour Disorder. J Pers Med, 11(11):1204. doi: 10.3390/jpm11111204.
• Onofrj M, Luciano AL, Thomas A, et al. (2003). Mirtazapine induces REM sleep behavior disorder in parkinsonism. Neurology, 60(1):113-5. doi: 10.1212/01.wnl.0000042084.03066.c0.
• https://www.michaeljfox.org/news/ask-md-acting-out-dreams-and-parkinsons-disease