Explore Causes of Restless Legs Syndrome

By Brandon Peters, MD

Although many people with restless legs syndrome (RLS) may never be able to identify a cause to their disorder, often it results from other secondary causes. This thus results in two categories of the condition, the former being primary RLS (of unknown cause) and the latter deemed secondary RLS. There are many conditions that may independently lead to symptoms of RLS and these are described here.

1. Iron Deficiency

The relationship between iron deficiency and RLS symptoms has been extensively studied. In several research studies, low iron levels have been found in the blood and spinal fluid of individuals suffering from RLS. The lower the iron levels, the worse the symptoms. Magnetic resonance imaging (MRI) has shown that the iron content in an area of the brain called the substantia nigra is lower in those with RLS compared to normal individuals, which may contribute to the disorder. In addition, pathological studies have confirmed this change within the brain.

It is therefore recommended that you have your serum ferritin level (a marker of iron stores) checked if you have symptoms of RLS. If the ferritin level is low, generally at a value <75, a trial of oral iron replacement should be undertaken. Even if the levels are normal, some individuals respond to iron replacement.

2. End-stage Kidney Disease

RLS is very common among individuals suffering from end-stage kidney disease, especially those who are dependent upon dialysis. The incidence has been reported to range from 6 to 60 percent. It is unclear what may be contributing to RLS in this group. Anemia, iron deficiency, or even low parathyroid hormone levels may have a role based on various studies. In some cases, treating anemia with erythropoietin therapy or iron replacement has been effective.

3. Diabetes

In people with Type 2 or adult-onset diabetes, RLS may develop. If diabetes is left uncontrolled, nerve damage can result. This is thought to occur because of high levels of glucose within the blood. This can lead to damage of small blood vessels that supply the nerves called vaso nervorum. When these become clogged, the nerve itself will become damaged. Often this leads to a peripheral neuropathy, which consists of pain and a pins-and-needles sensation in the feet. This may progress up the legs and even involve the hands. Associated with these sensory changes, some people will also have symptoms of RLS. Therefore, it is thought that diabetes may be an independent risk factor for developing RLS. In people who have undergone pancreas and kidney transplants, their symptoms of RLS have improved.

4. Multiple Sclerosis

There is a growing body of evidence that multiple sclerosis seems to be associated with an increased risk of having RLS. Some of the studies are conflicting, however. In one of the larger studies that included 1500 subjects, the prevalence of RLS was 19 percent in people with MS compared to only 4 percent of those people without it.

5. Parkinson’s Disease

It is thought that RLS and Parkinson’s disease may be caused by a similar problem, namely disruptions in the neurotransmitter called dopamine. This is not fully understood, however. Regardless, RLS may be present in individuals who have Parkinson’s disease, with a prevalence ranging from 0 to 20.8 percent, based on the study. Parkinson’s disease often involves a sense of restlessness (called akathisia) that may also occur in RLS, which may make it difficult to discriminate between the disorders. When both conditions are present, RLS usually occurs after Parkinson’s disease has become apparent.

6. Pregnancy

Not all conditions that may lead to RLS are disorders. In fact, the state of being pregnant seems to increase not only the incidence but also the degree of RLS symptoms. In a study of 626 pregnant women, only 10 percent had symptoms of RLS prior to becoming pregnant but this increased to 27 percent during pregnancy. It seemed to worsen in the third trimester. The good news is that the symptoms rapidly improved after delivery. It is not clear what causes the increased frequency of RLS during pregnancy. It may be due to iron or folate deficiency or even because of hormonal changes associated with being pregnant.

7. Rheumatic Disease

There are many conditions such as rheumatoid arthritis, Sjogren’s syndrome, and fibromyalgia that may have an association with symptoms of RLS. This relationship is unclear. In one study, 25 percent of individuals with rheumatoid arthritis had RLS symptoms compared to only 4 percent of osteoarthritis. In another study, 42 of 135 patients with fibromyalgia had RLS. The exact reason for this association is not fully understood.

8. Varicose Veins

In some instances, poor blood flow in the legs has been associated with RLS. In particular, weak veins that distend and become uncomfortable have been blamed. These so-called varicose veins are often engorged and blue in color and may be a sign of venous insufficiency. In a study of 1397 patients, 312 people complained of symptoms of RLS.

Treatment of varicose veins has proven to be effective in alleviating some of the symptoms of RLS. Sclerotherapy led to initial improvement in 98 percent of people, with relief maintained at two years in 72 percent. Medication treatment, including hyrdoxyethylrutoside, has also been shown to be modestly effective.

9. Other Conditions

Beyond the conditions described above, there are many other disorders that seem to be associated with RLS symptoms. These include:

• Obesity

• Obstructive sleep apnea

• Hypothyroidism

• High blood pressure

• Heart disease

• Peripheral neuropathies

• Vitamin deficiencies

• Excessive caffeine intake

• Low blood sugar

• Lumbosacral radiculopathy

• Spinal stenosis

• Use of mianserin (an antidepressant medication)

Sources:

Earley, CJ et al. “Abnormalities in CSF concentrations of ferritin and transferrin in restless legs syndrome.” Neurology 2000; 54:1698.

Allen, RP et al. “MRI measurement of brain iron in patients with restless legs syndrome.” Neurology 2001; 56:263.

Connor, JR et al. “Neuropathological examination suggests impaired brain iron acquisition in restless legs syndrome.” Neurology 2003; 61:304.

Kavanagh, D et al. “Restless legs syndrome in patients on dialysis.” Am J Kidney Dis 2004; 43:763.

Merlino, G et al. “Association of restless legs syndrome and quality of sleep in type 2 diabetes: a case-control study.” Sleep 2007; 30:866.

Manconi, M et al. “Multicenter case-control study on restless legs syndrome in multiple sclerosis: the REMS study.” Sleep 2008; 31:944.

Lee, JE et al. “Factors contributing to the development of restless legs syndrome in patients with Parkinson disease.” Mov Disord 2009; 24:579.

Manconi, M et al. “Restless legs syndrome and pregnancy.” Neurology 2004; 63:1065.

American Academy of Sleep Medicine. International Classification of Sleep Disorders. 3rd Edition Text Revision. 2024.

Walters, A. “Restless legs syndrome and periodic limb movements of sleep.” Continuum. Neurol 2007;13(3):115-138.

What Is Restless Legs Syndrome (RLS)?

By Brandon Peters, MD

Restless legs syndrome (RLS) is one of those conditions that sounds a little too strange to be true, but if you have ever laid down to fall asleep and felt an uncomfortable sensation of bugs crawling under your skin, you may be all too familiar with what RLS is. This condition may leave you kicking your legs as you fall asleep, but a better understanding of the disorder and its causes may lead to the treatment and rest that you need.

What is RLS?

RLS is a movement disorder that is characterized by unpleasant feelings in the legs associated with a need to move. The sensations (called paresthesias) may include aches, pulling, itching, or even the feeling of bugs crawling under the skin. The symptoms typically come on during periods of rest, especially at night, and are relieved by movement. They may make it hard to fall or stay asleep, resulting in insomnia.

There are four features that are used to diagnose RLS and these include:

1. An urge to move the legs, usually accompanied or caused by uncomfortable and unpleasant sensations in the legs.

2. The urge to move or unpleasant sensations begin or worsen during periods of rest or inactivity such as lying or sitting.

3. The sensations are relieved by movement, such as walking or stretching, as long as the activity continues.

4. The sensations are worse during the evening or night.

Symptoms typically come on within 15 to 30 minutes of resting. In very severe cases, the problems may occur with any seated activity during the day, such as sitting in meetings or in a movie theater. This may lead to fidgeting, constant movement, or the need to kick or massage the legs to relieve the symptoms. Some people are so bothered by the symptoms at night that they will get out of bed.

Individuals with RLS may experience periodic limb movements of sleep (PLMS), which consist of sudden jerking leg movements involuntarily during sleep.

How Common is RLS?

Mild symptoms associated with RLS occur in 5 to 15 percent of the population. It seems to increase as we get older and occurs more commonly in women.

There are two types of RLS. The first, called primary (or idiopathic) RLS, has no clear cause and tends to run in families. The other type, called secondary RLS, occurs as the result of separate conditions, including iron deficiency, diabetes, pregnancy, and more.

Diagnosis and Treatment of RLS

RLS is diagnosed using the four criteria described above. A sleep study called a polysomnogram is not necessary but it may be helpful if the condition is resistant to treatment. It is important to identify any contributing causes so that these can be addressed appropriately. The treatment of RLS may include iron replacement, a combination of medications (including those that enhance GABA or dopamine), exercises, and other therapies.

Sources:

Allen, RP et al. "Restless legs syndrome prevalence and impact: REST general population study." Arch Intern Med. 2003; 163:2323.

American Academy of Sleep Medicine. "International classification of sleep disorders: Diagnostic and coding manual." 3rd ed Text Revision. 2014.

Hogl, B et al. "Restless legs syndrome: a community-based study of prevalence, severity, and risk factors." Neurology. 2005; 64:1920.

💊 Medication Safety to Treat Sleep Disorders in Pregnancy: What You Need to Know

Sleep can be one of the first things to change when you're expecting. From hormone swings and nighttime bathroom trips to anxiety and physical discomfort, many pregnant people struggle to get the rest they need. While lifestyle changes and natural remedies help some, others may wonder: Is it safe to take medication for sleep during pregnancy?

The answer isn't black and white. Sleep medications should always be approached with caution during pregnancy, and not all are considered safe. In this post, we’ll explore what sleep medications may be used (and avoided) during pregnancy, natural alternatives, and when it’s time to talk to your doctor.

😴 Why Sleep Is So Important in Pregnancy

Sleep isn’t just about feeling rested—quality sleep supports a healthy pregnancy. Poor sleep has been linked to:

• Higher risk of gestational diabetes

• High blood pressure and preeclampsia

• Preterm birth

• Postpartum depression

• Increased labor difficulties

Because sleep is essential for both mom and baby, it’s understandable to want solutions when tossing and turning becomes the norm.

🚫 Why Sleep Medications Are Tricky During Pregnancy

Many over-the-counter (OTC) and prescription sleep aids haven’t been thoroughly tested for use during pregnancy. Some may impact fetal development, particularly in the first trimester when the baby's organs are forming.

The U.S. Food and Drug Administration (FDA) used to categorize medications by letter (A, B, C, D, X) for pregnancy safety. While that system is being phased out, it can still help frame the conversation:

• Category A & B: Generally considered safe

• Category C: Risk cannot be ruled out

• Category D & X: Known risks—avoid unless absolutely necessary

Let’s look at the most common sleep-related medications and how they fare in pregnancy.

✅ Sleep Aids Sometimes Used During Pregnancy

1. Diphenhydramine (Benadryl)

• Type: Antihistamine with sedative effects

• Pregnancy Category: B

• Common Use: Occasionally used to help with insomnia

• Caution: Long-term use is not recommended; may increase uterine activity close to labor

2. Doxylamine (Unisom SleepTabs)

• Type: Antihistamine

• Pregnancy Category: B

• Common Use: Safe in combination with vitamin B6 to treat morning sickness

• Note: Some providers suggest it short-term for sleep, but always consult your OB first

3. Melatonin

• Type: Hormone that regulates sleep cycles

• Pregnancy Category: Not officially categorized

• Status: Natural supplement, but safety in pregnancy is not well-established

• Note: Use with caution due to hormonal effects—talk to a healthcare provider before taking it

⚠️ Sleep Medications to Avoid or Use Only Under Strict Supervision

1. Prescription Benzodiazepines (e.g., Lorazepam, Diazepam)

• Pregnancy Category: D

• Risks: Linked to birth defects, withdrawal symptoms in newborns, and low birth weight

• Recommendation: Avoid unless prescribed for a serious condition under specialist care

2. Z-drugs (e.g., Zolpidem/Ambien)

• Pregnancy Category: C

• Risks: Some studies suggest links to preterm birth or breathing issues in newborns

• Use: May be prescribed if benefits outweigh risks, but not first-line treatment

3. Over-the-Counter Sleep Aids Containing Alcohol or Multiple Drugs

• Examples: NyQuil, Tylenol PM

• Concerns: Alcohol content, potential for overmedication

• Advice: Avoid unless recommended by your provider

🌿 Safer Alternatives: Non-Medication Options That Really Help

Before turning to medication, most providers recommend trying natural sleep aids and behavioral techniques, especially early in pregnancy.

🛌 Sleep Hygiene Tips:

• Go to bed and wake up at the same time every day

• Keep your bedroom cool, dark, and free of screens

• Avoid caffeine in the afternoon and evening

• Use relaxation techniques like breathing exercises, meditation, or prenatal yoga

🌼 Natural Remedies:

• Magnesium supplements (under doctor’s advice)

• Chamomile tea (in moderation)

• Lavender essential oil in a diffuser or pillow spray

• Guided meditation or sleep apps like Calm or Headspace

🩺 When to Talk to Your Doctor

If insomnia is affecting your daily function or contributing to depression, anxiety, or high blood pressure, it’s time to involve your healthcare provider. You don’t need to suffer through pregnancy sleeplessly—especially when there may be safe, effective solutions.

Your provider might recommend:

• Cognitive Behavioral Therapy for Insomnia (CBTI)

• Prenatal counseling to address stress or anxiety

• A short-term, carefully monitored sleep aid if the benefits outweigh the risks

💬 Final Thoughts

When it comes to sleep and pregnancy, medication isn’t off the table—but it should be approached with caution and professional guidance. Some sleep aids, like diphenhydramine or doxylamine, may be considered safe for occasional use, while others, especially prescription drugs, carry real risks.

The best approach? Start with lifestyle changes and non-drug strategies, and talk openly with your doctor if sleep continues to be a struggle. With the right tools and support, restful nights can be part of your pregnancy journey.

This article was created using OpenAI’s ChatGPT on July 11, 2025 and it was personally reviewed and edited by Brandon Peters, M.D. to ensure its accuracy. This use of augmented intelligence in this way allows the creation of health information that can be trusted.

😴 How Sleep Changes During Pregnancy: What to Expect Trimester by Trimester

Sleep is something we often take for granted—until it becomes elusive. For many women, pregnancy brings unexpected challenges when it comes to getting a good night’s rest. While some may assume sleep disturbances only happen in the third trimester, the reality is that sleep changes throughout pregnancy, starting as early as the first few weeks.

In this post, we’ll break down how and why your sleep might change across each trimester, what causes those disruptions, and how you can manage them for a healthier, more restful pregnancy.

🌙 First Trimester (Weeks 1–12): Surprising Sleepiness and Strange Dreams

What Happens to Sleep?

In the first trimester, many women feel overwhelmingly tired—even if they’re sleeping more than usual. That exhaustion stems from a surge in progesterone, a hormone that supports early pregnancy and also has a natural sedative effect. You might find yourself napping during the day or struggling to keep your eyes open in the afternoon.

However, paradoxically, some women also report insomnia, vivid dreams, and frequent nighttime awakenings during this time.

Common Sleep Disruptions:

• Increased fatigue during the day

• Frequent nighttime urination due to hormonal changes

• Breast tenderness making it uncomfortable to sleep in usual positions

• Nausea (especially if it strikes at night)

• Emotional changes or anxiety interfering with falling asleep

Tips for Better Sleep in the First Trimester:

• Nap if needed, but keep naps under 30 minutes to avoid nighttime wakefulness

• Drink fluids early in the day, and taper off in the evening

• Use supportive pillows to ease breast discomfort

• Practice calming bedtime rituals—meditation, light reading, or a warm bath

🌜 Second Trimester (Weeks 13–27): The Sleep "Sweet Spot"

What Happens to Sleep?

For many women, the second trimester is a bit of a reprieve. Morning sickness usually fades, energy levels improve, and hormonal swings stabilize somewhat. This can make it easier to sleep soundly at night and feel more like yourself during the day.

However, not all sleep disturbances vanish. Heartburn, leg cramps, and the beginnings of a growing belly can still cause occasional trouble.

Common Sleep Disruptions:

• Mild heartburn or indigestion

• Leg cramps or restless leg syndrome (RLS)

• Back pain or mild discomfort from a growing belly

• Increased vivid dreaming or nightmares

Tips for Better Sleep in the Second Trimester:

• Begin sleeping on your left side, which promotes better circulation to your baby

• Place a pillow between your knees or under your belly for support

• Eat smaller meals to reduce heartburn

• Stretch gently before bed to prevent leg cramps

🌘 Third Trimester (Weeks 28–40): When Sleep Gets Tough

What Happens to Sleep?

The third trimester is when sleep challenges really peak. As your baby grows and your body prepares for labor, both physical and emotional discomforts make it harder to fall—and stay—asleep.

You might find yourself waking up multiple times a night, tossing and turning, or simply lying awake due to discomfort or anxiety.

Common Sleep Disruptions:

• Frequent urination, sometimes every hour

• Back pain and general discomfort from baby’s position

• Kicks or fetal movements that wake you up

• Heartburn or acid reflux

• Anxiety about labor, delivery, or parenthood

• Snoring or mild sleep apnea, due to nasal congestion and weight gain

Tips for Better Sleep in the Third Trimester:

• Sleep propped up with extra pillows to ease heartburn

• Try prenatal yoga or light stretching to reduce tension

• Avoid spicy or acidic foods close to bedtime

• Use white noise or calming sounds to help you relax

• Talk to your doctor if snoring or sleep apnea becomes frequent

🧘‍♀️ Safe Sleep Strategies for All Trimesters

No matter where you are in your pregnancy, a few consistent habits can support better sleep:

✅ Create a Relaxing Bedtime Routine

Signal to your brain that it’s time to wind down with calming rituals: dim the lights, avoid screens, read a book, or try guided meditation.

✅ Avoid Sleep Aids Unless Prescribed

While it may be tempting to reach for an over-the-counter sleep aid, always consult your healthcare provider first. Many common medications are not safe during pregnancy.

✅ Stay Active (But Not Too Late)

Regular, moderate exercise during the day can improve sleep—but avoid intense workouts too close to bedtime.

✅ Manage Worries

Pregnancy brings big changes, and anxiety is normal. Journaling, talking to a friend, or seeing a therapist can help reduce bedtime overthinking.

🩺 When to Talk to Your Doctor

Occasional sleep disruptions are normal during pregnancy, but chronic insomnia, extreme fatigue, or symptoms like severe snoring or leg jerking may point to deeper issues, such as:

• Sleep apnea

• Restless leg syndrome

• Prenatal depression or anxiety

Always discuss persistent sleep problems with your doctor or midwife—they may refer you to a sleep specialist or recommend safe, pregnancy-appropriate treatments.

🛌 Final Thoughts

Sleep and pregnancy have a complicated relationship. From first-trimester fatigue to third-trimester discomfort, each stage brings its own unique sleep challenges.

While you can’t prevent all sleep disturbances, understanding what to expect—and how to adapt—can make a big difference in your comfort and overall well-being.

Remember: you're growing a whole new human. Be gentle with yourself, rest when you can, and don’t hesitate to ask for help. Sleep may be elusive at times, but your body (and your baby) will thank you for every hour you can get.

📣 What’s Been Your Experience with Sleep During Pregnancy?
Let us know in the comments! Sharing your story could help another mama-to-be feel less alone.

This article was created using OpenAI’s ChatGPT on July 11, 2025 and it was personally reviewed and edited by Brandon Peters, M.D. to ensure its accuracy. This use of augmented intelligence in this way allows the creation of health information that can be trusted.

💤 Can Insomnia Be an Early Sign or Symptom of Pregnancy?

Pregnancy is a life-changing journey, and with it come a variety of emotional and physical changes—some expected, some surprising. While most people associate later stages of pregnancy with sleep troubles, some women notice something odd even earlier: insomnia.

But can insomnia really be an early sign of pregnancy? Let’s explore the science, symptoms, and what you can do if you're struggling to sleep during those early weeks.

🧠 What Is Insomnia?

Insomnia is the inability to fall asleep, stay asleep, or return to sleep after waking. It can be acute (short-term) or chronic (long-lasting), and it’s caused by a wide variety of factors:

• Stress

• Hormonal shifts

• Medical conditions (i.e., sleep apnea, pain)

• Lifestyle habits (i.e., caffeine, alcohol, napping)

When you're trying to conceive—or unexpectedly find yourself feeling “off”—sudden sleep disturbances may be one of your body's earliest hints.

🌙 Is Insomnia an Early Pregnancy Symptom?

Although it’s not one of the most common signs of early pregnancy like nausea or a missed period, some women do experience insomnia in the first few weeks. Here's why:

1. Hormonal Changes

Pregnancy triggers a surge of hormones, including progesterone and estrogen:

• Progesterone can make you sleepy during the day but cause fragmented or restless sleep at night.

• Estrogen influences sleep-regulating neurotransmitters like serotonin, which can affect your ability to fall asleep.

2. Increased Urination

The pregnancy hormone hCG increases blood flow to your kidneys, making you urinate more often—even in the first few weeks. Frequent nighttime bathroom trips can seriously disturb your sleep.

3. Anxiety and Emotional Changes

Even in a planned pregnancy, early emotions can be intense. Worries about the future, the baby’s health, or life changes ahead can cause racing thoughts, making it hard to drift off.

4. Mild Physical Discomfort

Tender breasts, bloating, and light cramping are all normal early signs of pregnancy. These symptoms, while not intense, can make sleeping difficult or uncomfortable.

5. Increased Body Temperature

Many women notice a rise in basal body temperature after ovulation and into early pregnancy. Feeling warmer at night or sweating more than usual can affect sleep quality.

🤔 Could It Be Something Else?

Not every case of insomnia signals pregnancy. Sleep issues are incredibly common and can be caused by:

• Stress or lifestyle changes

• Diet (caffeine, alcohol)

• Screen time before bed

• Menstrual cycle fluctuations

However, if your insomnia is accompanied by symptoms like:

• Missed period

• Fatigue

• Nausea

• Breast tenderness

• Mood swings

• Mild pelvic cramping

…it might be worth taking a pregnancy test.

📊 How Common Is Early Pregnancy Insomnia?

While most studies focus on sleep problems in the second and third trimesters, many women report changes in their sleep in the first few weeks.

Sleep disruptions—including trouble falling asleep and night waking—are very common throughout pregnancy, beginning as early as the first trimester.

🛏️ Tips for Managing Insomnia in Early Pregnancy

If you're pregnant—or think you might be—and insomnia is keeping you up, here are some natural, pregnancy-safe tips to help you sleep better:

1. Practice Good Sleep Hygiene

• Stick to a consistent sleep schedule

• Avoid screens 30–60 minutes before bed

• Keep your bedroom cool, dark, and quiet

2. Limit Fluids in the Evening

Drink plenty of water during the day, but reduce your intake in the evening to prevent frequent nighttime bathroom trips.

3. Try Relaxation Techniques

• Deep breathing

• Meditation apps

• Prenatal yoga

• Progressive muscle relaxation

4. Eat Smart

Avoid heavy meals late at night. Eat a light, protein-rich snack if nausea or hunger is waking you up.

5. Manage Anxiety

Talk to a friend or partner about your worries. Journaling or seeking support from a counselor can help reduce nighttime overthinking.

🩺 When to Call a Doctor

If you’re experiencing chronic insomnia—trouble sleeping for more than three nights a week for several weeks—or if sleep issues are causing severe fatigue, mood swings, or anxiety, it’s time to consult your doctor.

There are safe and effective treatments for sleep issues during pregnancy, including cognitive behavioral therapy for insomnia (CBTI) and lifestyle adjustments. Avoid taking over-the-counter sleep aids unless recommended by your healthcare provider.

✅ Final Thoughts

So, can insomnia be an early sign of pregnancy? Yes—it can, for some women. Hormonal changes, emotional shifts, and early physical symptoms can all contribute to disrupted sleep in the first few weeks.

However, insomnia on its own isn't a definitive sign of pregnancy. If it’s accompanied by other early symptoms, it may be worth testing and speaking with your doctor.

Regardless of the cause, quality sleep is essential—especially during pregnancy. Prioritize rest, listen to your body, and don’t hesitate to seek support if you're struggling.

This article was created using OpenAI’s ChatGPT on July 11, 2025 and it was personally reviewed and edited by Brandon Peters, M.D. to ensure its accuracy. This use of augmented intelligence in this way allows the creation of health information that can be trusted.