What Is Restless Legs Syndrome?
Sleep disorders are a disruption in an individual’s sleep quality, timing and duration of sleep hours. These sleep pattern conditions negatively impact overall health. Examples of sleep disorders are insomnia, narcolepsy, restless legs syndrome (RLS) and sleep apnea.
Restless legs syndrome (RLS)—also known as Willis-Ekbom disease, primary RLS and idiopathic RLS—is a neurological disorder that causes unpleasant or uncomfortable sensations in your legs and an irresistible urge to move them. Symptoms commonly occur in the late afternoon or evening hours and are often most intense at night when you are resting. RLS can severely disrupt your sleep, making it difficult to fall asleep or return to sleep after waking up. Moving the legs or walking typically relieves the discomfort but the sensations often recur once the movement stops.
RLS is both a sleep disorder, because the symptoms are triggered by resting and attempting to sleep, and a movement disorder, because people with RLS are forced to move their legs in order to relieve symptoms.
It is estimated that up to 7 to 10 percent of the U.S. population may have RLS, which can begin at any age. It occurs in both males and females, although females are more likely to have it. Many individuals who are severely affected are middle-aged or older, and the symptoms typically become more frequent and last longer with age.
RLS is generally a lifelong condition for which there is no cure. However, treatments are available to ease symptoms.
RLS is characterized by an unpleasant “creeping” sensation, often feeling like it is originating in the lower legs, but often associated with aches and pains throughout the legs. This often causes difficulty initiating sleep and is relieved by movement of the legs, such as walking or kicking. Abnormalities in the neurotransmitter dopamine have often been associated with RLS. Healthcare providers often combine a medication to help correct the underlying dopamine abnormality along with a medicine to promote sleep continuity in the treatment of RLS.
Types of Restless Legs Syndrome
Sleep-related difficulties affect many people. If you, or someone you know, is experiencing any of the following, it is important to receive an evaluation by a healthcare provider or, if necessary, a provider specializing in sleep medicine.
Restless legs syndrome (RLS) is characterized by an unpleasant “creeping” sensation, often feeling like it is originating in the lower legs, but often associated with aches and pains throughout the legs. This often causes difficulty initiating sleep and is relieved by movement of the legs, such as walking or kicking.
There are two types of restless legs syndrome, primary restless legs syndrome and secondary restless legs syndrome. Commonly, RLS is a primary central nervous system disorder and is familial, or inherited, in between 25 and 75 percent of patients.
Secondary restless legs syndrome can occur as a symptom to other disorders, including:
- Iron deficiency
- End-stage renal disease
- Diabetes mellitus
- Rheumatic disease
- Venous insufficiency
- Peripheral neuropathy
- Folate or magnesium deficiency
- Amyloidosis
- Lumbosacral radiculopathy
- Fibromyalgia
- Celiac disease
- Pregnancy (with symptoms resolving a few weeks after delivery)
- Medications have been known to cause or exacerbate the symptoms of restless legs syndrome. They include antidopaminergic medications (e.g., neuroleptics), diphenhydramine, tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), alcohol, caffeine, lithium and beta-blockers.
Causes of Restless Legs Syndrome
In most cases, the cause of restless legs syndrome (RLS) is unknown. However, RLS often runs in families and specific gene variants have been associated with the condition. Low levels of iron in the brain also may be responsible for RLS.
RLS also may be related to a dysfunction in a part of your brain that controls movement. The basal ganglia uses the brain chemical dopamine to produce smooth, purposeful muscle activity and movement. Disruption of dopamine levels in the brain frequently results in involuntary movements. Individuals living with the movement disorder Parkinson’s disease have an increased risk of developing RLS.
RLS also appears to be related to or accompany the following factors or underlying conditions:
- End-stage renal disease and hemodialysis
- Neuropathy (nerve damage)
- Sleep deprivation and other sleep conditions such as sleep apnea
- Pregnancy or hormonal changes, especially in the last trimester. In most cases, symptoms usually disappear within four weeks after delivery.
- Use of alcohol, nicotine and caffeine
Certain medications may aggravate your RLS symptoms, such as some anti-nausea drugs, antipsychotic drugs, antidepressants that increase serotonin, and cold and allergy medications that contain older antihistamines.
Risk Factors for Restless Legs Syndrome
RLS also may be related to a dysfunction in a part of your brain that controls movement. The basal ganglia uses the brain chemical dopamine to produce smooth, purposeful muscle activity and movement. Disruption of dopamine levels in the brain frequently results in involuntary movements. Individuals living with the movement disorder Parkinson’s disease have an increased risk of developing RLS.
RLS also appears to be related to or accompany the following factors or underlying conditions:
- End-stage renal disease and hemodialysis
- Neuropathy (nerve damage)
- Sleep deprivation and other sleep conditions such as sleep apnea
- Pregnancy or hormonal changes, especially in the last trimester. In most cases, symptoms usually disappear within four weeks after delivery.
- Use of alcohol, nicotine and caffeine
Certain medications may aggravate your RLS symptoms, such as some anti-nausea drugs, antipsychotic drugs, antidepressants that increase serotonin, and cold and allergy medications that contain older antihistamines.
Screening for & Preventing Restless Legs Syndrome
Screening for sleep disorders such as restless leg syndrome (RLS) involves participating in a sleep study using surveillance systems to monitor sleep duration and quality.
You might also complete a questionnaire that asks the following questions:
- On average, how many hours of sleep do you get in a 24-hour period?
- Over the past two weeks, how many days have you had trouble falling asleep or staying asleep?
- Over the past two weeks, how many days did you unintentionally fall asleep during the day?
- Have you ever been told that you snore loudly?
- Has anyone ever observed that you stop breathing during your sleep?
Prevention of RLS may be helped by regular, moderate exercise, stretching, relaxation exercises, cessation of smoking, warm baths or using heating pads on the legs. Additionally, supplements like folate, iron and ferritin may be helpful for pregnancy-related RLS symptoms.
Signs & Symptoms of Restless Legs Syndrome
Restless leg syndrome (RLS) is characterized by an unpleasant “creeping” sensation, often feeling like it is originating in the lower legs, but often associated with aches and pains throughout the legs. This often causes difficulty initiating sleep and is relieved by movement of the legs, such as walking or kicking.
If you have RLS, you may feel an irresistible urge to move, which is accompanied by uncomfortable sensations in your lower limbs that are unlike normal sensations experienced by someone without the disorder. The sensations in your legs may feel like aching, throbbing, pulling, itching, crawling or creeping. These sensations less commonly affect the arms, and rarely the chest or head. Although the sensations can occur on just one side of your body, they most often affect both sides.
Common characteristics of RLS include:
- Sensations that begin after rest: They typically occur when you are inactive and sitting for extended periods (e.g., when taking a trip by plane or watching a movie).
- Relief of discomfort with movement: You may need to keep your legs (or other affected parts of the body) in motion to minimize or prevent the sensations. You might need to pace the floor or constantly move your legs while sitting.
- Worsening of symptoms at night with a distinct symptom-free period in the early morning: You might have difficulty falling asleep and staying asleep. You may also note a worsening of symptoms if your sleep is further reduced by events or activity.
RLS symptoms may vary from day to day, in severity and frequency, and from person to person. With moderately severe RLS, your symptoms might only occur once or twice a week but often result in significant delay of sleep onset, with some disruption of daytime function. In severe cases of RLS, the symptoms occur more than twice a week.
RLS can cause you to experience the following:
- Changes in mood
- Exhaustion and daytime sleepiness
- Problems concentrating
- Impaired memory
- Decreased productivity
- Depression and anxiety
You might experience remissions—periods in which symptoms decrease or disappear for weeks or months—usually during the early stages of the disorder. In general, however, symptoms often reappear and become more severe over time.
Is periodic limb movement of sleep the same or different from RLS?
More than 80 percent of people with RLS also experience periodic limb movement of sleep (PLMS). PLMS is characterized by involuntary leg (and sometimes arm) twitching or jerking movements during sleep that typically occur every 15 to 40 seconds, sometimes throughout the night. Although many individuals with RLS also develop PLMS, most people with PLMS do not experience RLS.
Diagnosing Restless Legs Syndrome
There is no specific test for RLS, so the condition is diagnosed by a doctor’s evaluation. The five basic criteria for clinically diagnosing RLS include:
- A strong and often overwhelming need or urge to move your legs that is often associated with abnormal, unpleasant or uncomfortable sensations.
- The urge to move your legs starts or gets worse during rest or inactivity.
- The urge to move your legs is at least temporarily and partially or totally relieved by movements.
- The urge to move your legs starts or is aggravated in the evening or night.
- The above four features are not due to any other medical or behavioral condition.
A neurological and physical exam, plus information about your medical and family history and list of current medications, may be helpful. You should talk with your doctor about the frequency, duration and intensity of your symptoms—if movement helps to relieve them; how much time it takes to fall asleep; any pain related to symptoms; and, any tendency toward daytime sleep patterns and sleepiness, disturbance of sleep, or daytime function.
Blood tests may rule out other conditions that may be causing your RLS symptoms, such as kidney failure, low iron levels and other causes of sleep disruption, such as sleep apnea and pregnancy. In fact, about 25 percent of pregnant females develop RLS but the symptoms often disappear after giving birth.
Diagnosing RLS in children may be especially difficult as it may be hard for children to describe their symptoms. Pediatric RLS can sometimes be misdiagnosed as "growing pains" or attention-deficit/hyperactivity disorder.
Treating Restless Legs Syndrome
There is no cure for RLS, but some symptoms can be treated. Moving your affected limb(s) may provide temporary relief. Sometimes RLS symptoms can be controlled by treating an associated medical condition, such as peripheral neuropathy, diabetes or iron-deficiency anemia.
Medications for RLS include:
- Iron supplements
- Anti-seizure drugs: Anti-seizure drugs are the first-line prescription drugs for those with RLS. The U.S. Food and Drug Administration (FDA) approved gabapentin enacarbil for the treatment of moderate to severe RLS. Other anti-seizure drugs such as pregabalin can decrease such sensory disturbances and nerve pain.
- Dopaminergic agents: These drugs, which increase dopamine in the brain, can reduce symptoms of RLS when taken at night. The medications ropinirole, pramipexole and rotigotine are FDA-approved to treat moderate to severe RLS. Levodopa plus carbidopa may be effective when used intermittently, but not daily, because long-term use of dopaminergic drugs can eventually worsen symptoms and cause other complications.
- Opioids: Drugs such as methadone, codeine, hydrocodone or oxycodone are sometimes prescribed to treat individuals with more severe symptoms of RLS who do not respond well to other medications.
- Benzodiazepines: Medications such as clonazepam and lorazepam are generally prescribed to treat anxiety, muscle spasms and insomnia, and can help individuals get more restful sleep.
The following lifestyle changes and activities may provide some relief if you have mild to moderate RLS:
- Avoid or decrease the use of alcohol, nicotine and caffeine
- Change or maintain a regular sleep pattern
- Try moderate, regular exercise
- Massage the legs or take a warm bath
- Apply a heating pad or ice pack
- Use foot wraps specially designed for people with RLS, or vibration pads to the back of the legs
- Do aerobic and leg-stretching exercises of moderate intensity
Living with Restless Legs Syndrome
The National Institute of Neurological Disorders and Stroke (NINDS) is the primary federal funding agency for research on restless legs syndrome. NINDS is a component of the National Institutes of Health (NIH), a leading supporter of biomedical research in the world.
- Researchers are investigating changes in the brain’s signaling pathways that are likely to contribute to RLS. In particular, researchers suspect that impaired transmission of dopamine in the brain’s basal ganglia may play a role. Researchers also hope to discover genetic relationships in RLS and to better understand what causes the disease.
- NINDS-funded researchers are studying the role of epigenetics in RLS development. Epigenetic changes can switch genes on or off, which can broadly affect both health and disease. Evidence suggests that iron deficiency during pregnancy, infancy and childhood increases the risk of developing RLS later in life. Scientists hope that understanding epigenetic changes associated with iron deficiency can offer new information on how to prevent RLS.
- NINDS also supports research on why the use of dopamine agents to treat RLS, Parkinson’s disease, and other movement disorders can lead to impulse control disorders, with aims to develop new or improved treatments that avoid this adverse side effect.
- NINDS-funded researchers are using advanced magnetic resonance imaging (MRI) to measure brain chemical changes in the brain’s arousal system in individuals with RLS to develop new research models and ways to correct the overactive arousal process.
- Scientists currently do not fully understand the mechanisms through which iron gets into the brain and how those mechanisms are regulated. NINDS-funded researchers are studying the role of endothelial cells—part of the protective lining called the blood-brain barrier that separates circulating blood from the fluid surrounding brain tissue—in the regulation of cerebral iron metabolism. Results may offer new insights into treating the cognitive and movement symptoms associated with RLS.
- Researchers are also testing non-drug therapies such as a compact, wearable non-invasive nerve stimulation device designed to treat RLS during sleep.
More information about research on RLS supported by NINDS or other components of the NIH is available through the NIH RePORTER, a searchable database of current and previously funded research, as well as research results such as publications.
For research articles and summaries on RLS, search PubMed, which contains citations from medical journals and other sites.