If you’ve ever struggled with sleep and Parkinson’s, you know how confusing and frustrating it can be. From insomnia to daytime sleepiness, sleep challenges are common — but clear guidance on what actually helps isn’t always easy to find.
To get clarity on this topic, Rachel Dolhun, MD, DipABLM, principal medical advisor at The Michael J. Fox Foundation, spoke with Michelle Jonelis, MD, DBSM, DipABLM, a sleep and lifestyle medicine physician and the founder and medical director of Lifestyle Sleep — a lifestyle-focused sleep medicine clinic in the San Francisco Bay Area of California — to answer the most common questions about Parkinson’s and sleep.
Rachel Dolhun, MD, DipABLM (RD): What is a circadian rhythm, and how does Parkinson’s affect it?
Michelle Jonelis, MD, DBSM, DipABLM (MJ): A circadian rhythm is a predictable, roughly 24-hour pattern in how the brain and body function. It influences sleep and wakefulness, hormone secretion, digestion, blood pressure, body temperature, memory and thinking (cognition), and movement.
The circadian system is coordinated by a small region in the brain called the suprachiasmatic nucleus, or SCN. The SCN integrates signals from light exposure, physical activity, meals, social interaction and daily routines. Based on these inputs, the SCN tells the brain and body when to carry out different functions during the day and night.
In Parkinson’s disease, the circadian system can be disrupted in two ways. First, the disease itself affects pathways that carry signals into and out of the SCN. As a result, outside cues such as light and activity are transmitted less effectively into the circadian clock, and the clock’s output signals are weakened. This makes it harder for the brain and body to maintain stable day-night rhythms, affecting not only sleep and wakefulness but also other processes that should differ between daytime and nighttime, such as digestion, blood pressure and movement.
Second, Parkinson’s often leads to lifestyle changes that also weaken circadian signaling. As symptoms progress, people may become less physically active, spend less time outdoors, socialize less or follow a less structured daily routine. These changes reduce the external cues that help anchor the circadian system.
When circadian rhythms weaken, sleep can become lighter, more fragmented and more likely to intrude on daytime wakefulness. Importantly, this does not mean that sleep itself is broken or needs to be forced. Rather, the signals telling the body when to sleep and when to be awake have become less reliable and need to be reinforced.
Research shows that reinforcing time cues through consistent routines such as regular light exposure, predictable meal timing, daily physical activity, social engagement, and stable bed and wake times can improve sleep and daytime alertness in Parkinson’s and may even have favorable effects on disease progression.
Watch my Ask the MD video to learn more about getting your best sleep with Parkinson’s.
RD: What is light therapy? Is it helpful in Parkinson’s?
MJ: Light therapy is intentional exposure to bright light via the outdoors, a light lamp or box, or a combination. The goal is to mimic the pattern of natural sunlight and strengthen circadian rhythm.
Light is the most powerful signal to the brain’s circadian clock. For most of human history, this signal came almost entirely from the sun. We now spend close to 90 percent of our time indoors, dramatically weakening this signal. Reduced daylight exposure is associated with lower vitamin D levels, higher blood pressure, nearsightedness, poorer sleep quality and impaired mood and attention. In those with Parkinson’s disease, where circadian signaling may already be compromised, insufficient light exposure can have even greater consequences. Part of this may be because bright light not only affects circadian rhythm but also may enhance brain dopamine signaling.
The best form of light therapy, when possible, is natural outdoor light. Being outside provides much higher light intensity than indoor lighting and adds benefits of physical movement and sensory stimulation. However, Parkinson’s is associated with an increased risk of skin cancer (melanoma) and impaired body temperature regulation, so sun safety is important: Avoid peak midday sun, monitor for overheating, wear sun protective clothing or a wide brimmed hat, and use sunscreen when necessary.
When outdoor light exposure is not feasible or sufficient, bright light therapy devices may be an option. Research studies in Parkinson’s show light therapy is associated with better sleep, reduced daytime sleepiness, improved mood and, in some cases, improved motor symptoms. Studies have used a range of protocols, most commonly involving 10,000 lux light exposure for anywhere from 30 minutes once daily to one hour twice daily.
This makes it hard to offer specific guidance. A starting point may be to aim for one hour of bright light in the morning between 9 and 10 a.m. and another hour in the afternoon between 3 and 4 p.m. If you use light therapy devices, do so under your doctor’s guidance, increasing gradually, as tolerated, to a maximum of two hours per day at full brightness. Most people can extend time outdoors safely (with sun and temperature precautions), as much as possible, and research suggests that benefits continue to increase the more you’re outdoors.
RD: What sleep medications are effective for Parkinson’s? Which should you avoid?
MJ: Taking a sleeping pill may provide temporary relief, but it does not address the underlying causes. It is like using medication to reduce a fever. You may feel better briefly, but the root problem remains. The most effective sleep treatments focus on strengthening circadian rhythms; adjusting medication and/or timing where needed; treating any underlying sleep disorders such as sleep apnea; and optimizing daytime habits. Cognitive behavioral therapy for insomnia (CBT-I), a type of talk therapy that involves sleep coaching, may also be helpful for people with Parkinson’s who have trouble falling or staying asleep.
In general, traditional sleeping pills (such as zolpidem or Ambien) are not ideal for people with Parkinson’s. Most of these medications work as sedatives, meaning they slow down brain functioning. This can worsen cognition, balance and daytime alertness.
There is one sleep condition in Parkinson’s where sleep medication may help. That is REM Sleep Behavior Disorder, or RBD, where people act out their dreams. In this case, melatonin and/or clonazepam can be helpful or even necessary for safety.
RD: How do you define a “good” night's sleep for someone with Parkinson's?
MJ: Sleep is an automatic process that emerges from a complex interplay of internal and external factors such as genetics, age, light exposure, physical activity, social rhythms, stress levels and diet. Sleep is not something we achieve through effort; it happens when the conditions are right. While we cannot control sleep itself, we can influence the conditions that support it.
For people with Parkinson’s, healthy sleep is less about the number of hours of uninterrupted sleep and more about patterns and how sleep supports daytime function. Part of healthy sleep is feeling refreshed and able to engage in daily activities. Persistent fatigue does not necessarily mean your sleep is poor, as Parkinson’s itself, medications and other health or lifestyle factors can contribute to fatigue and daytime sleepiness.
Ways that you can support healthy sleep include:
Strengthen circadian and lifestyle habits: Wake up and go to bed at a consistent time each day, ideally within an hour and even on weekends. Spend time outdoors in natural light, engage in regular physical activity and include social and mentally stimulating activities in your daily routine. Eat a diet rich in plants while limiting added sugars and ultra-processed foods. Be aware that substances such as caffeine, nicotine, alcohol and cannabis can interfere with both sleep and daytime alertness.
Give appropriate sleep opportunity: Allow enough time in bed to fall asleep within about 30 minutes and not feel excessively sleepy during the day. Spending too long in bed can worsen nighttime wakefulness; sometimes reducing time in bed improves sleep quality.
Allow flexible, natural variation: Some nights, sleep may be lighter and shorter, or you may have more awakenings. Other nights, sleep may be deeper or longer. Sleep naturally fluctuates based on stress, recent sleep or napping, daytime activity, mood and other factors. Brief awakenings or awareness during the night are normal and can be protective, allowing you to use the bathroom or change position for comfort. (Research also suggests these awakenings increase naturally with age.) Night is a time for both rest and sleep and the proportions of each will vary on any given night.
Manage naps strategically: Short naps of 20 to 60 minutes in the early afternoon can be helpful. On the other hand, multiple naps throughout the day or for more than an hour per day can disrupt nighttime sleep. (They also may indicate that circadian or overall health is not optimized, meaning there are steps you can take to help sleep.)
The most important point is: Try not to stress about sleep itself. (And that takes practice!) Try to view sleep as a natural byproduct of the right conditions and focus on optimizing the conditions that support it: consistent routines, regular light exposure, movement, meal timing and social engagement. These habits strengthen the body’s natural rhythms and improve both nighttime rest and daytime function.
RD: How can you manage feeling sleepy during the day?
MJ: Many people assume that daytime sleepiness results directly from poor nighttime sleep, but the relationship is more complex. In many cases, nighttime disruption is actually caused by daytime factors such as excessive napping, low activity or limited exposure to bright light. Increasing daytime engagement, movement and time in natural light can improve both nighttime sleep and daytime alertness.
Other common contributors to both sleeplessness and daytime drowsiness include obstructive sleep apnea; medications; or environmental factors such as noise, light or an overly warm bedroom. Additionally, stress can disrupt sleep and increase fatigue by activating the “fight or flight” (sympathetic nervous) system, and a diet high in sugar and refined carbohydrates can interfere with the hormones that regulate sleep and wakefulness.
The key to managing daytime drowsiness and nighttime sleeplessness is focusing on what you can influence. A few examples:
Review medications: Some Parkinson’s drugs, such as dopamine agonists, can cause daytime sleepiness. Others, such as amantadine, MAO-B inhibitors or rivastigmine, can increase wakefulness or disrupt sleep. Adjusting timing, dose or type may help.
Screen for and treat obstructive sleep apnea, especially if you snore: A sleep study and appropriate therapy can improve both nighttime sleep and daytime alertness.
Keep your bedroom cool, dark and quiet.
Limit stress: Mindfulness, relaxation exercises or other stress management techniques can reduce sympathetic nervous system overactivation, improving sleep quality and daytime energy.
RD: Is melatonin helpful for sleep in Parkinson’s?
MJ: Melatonin is a hormone produced by the brain in response to darkness. When the eyes no longer detect sunlight, melatonin rises, signaling that it is time for the body to shift into nighttime mode. Historically, this meant melatonin levels rose after sunset and remained elevated until morning. In modern environments, artificial lighting after dark, particularly blue light from computer and phone screens, can suppress melatonin release. In addition, insufficient exposure to bright light during the day can weaken melatonin production at night.
In Parkinson’s disease, the strongest evidence for melatonin use is to treat REM Sleep Behavior Disorder (RBD), a condition in which people act out their dreams. Multiple studies show that melatonin can reduce dream enactment and improve safety during sleep. The typical dose is 3 to 15 mg of immediate release melatonin taken around bedtime, starting low and increasing gradually, as needed, while keeping a log of dream enactment events. Because melatonin is sold as an over-the-counter supplement in the United States, product quality can vary. Choose a formulation that is third-party tested to ensure more reliable dosing.
Outside of RBD, some studies suggest that melatonin may modestly improve how people with Parkinson’s feel they sleep. However, most studies show little to no change in objective sleep measures, such as total minutes slept, depth of sleep and wakefulness during the night. This suggests that while some people feel that they sleep better, the structure and duration of sleep may not change substantially. A few studies have also reported small improvements in certain motor or non-motor symptoms, but these effects are generally modest.
Unlike many traditional sleep medications, melatonin is not a sedative and does not impair cognition, balance or motor function. For general sleep support, typical doses range from 0.5 to 10 mg taken in the evening or at bedtime. Higher doses are not necessarily more effective and can worsen sleep or cause next-day grogginess. If melatonin is helpful, it is generally safe for long term use.
It is important to note that nighttime melatonin production is strongly influenced by daytime habits. Bright light exposure during the day, regular physical activity, a plant-rich diet, stress reduction, limiting exposure to blue light in the evening and sleeping in a dark environment all support melatonin release. For many people, optimizing these factors is more effective than taking melatonin as a supplement.
RD: What do you wish people with Parkinson’s understood better about sleep?
MJ: Sleep is not something you can force through effort or willpower. Sleep is an automatic process that happens when conditions are right. In fact, trying harder to sleep often makes sleep worse. When healthcare providers and public health messaging emphasize the importance of sleep for health, what they are really referring to is the importance of healthy sleep habits, not perfect or effortless sleep.
What people do have control over are the conditions that support sleep. Light exposure, physical activity, daily routines, social engagement, diet, medication timing and how much time is spent in bed all strongly influence the brain’s sleep-wake systems.
When sleep disruption is viewed as a symptom rather than a personal failure or something to “fix” with a pill, it may become less frustrating and more treatable. By focusing on strengthening the circadian rhythm and supporting the body’s natural sleep-wake processes, many people may be able to achieve reasonably healthy sleep and feel better during the day as well.
Learn more about a major expanded global research effort to better understand Parkinson’s disease and move us closer to more effective, personalized treatments.
The medical information contained in this publication is for general information purposes only. The Michael J. Fox Foundation for Parkinson’s Research has a policy of refraining from advocating, endorsing or promoting any drug therapy, course of treatment, or specific company or institution. It is crucial that care and treatment decisions related to Parkinson’s disease and any other medical condition be made in consultation with a physician or other qualified medical professional, such as a sleep specialist.
