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Harvard Health Publications

Restless Legs Syndrome

What Is It?

Restless legs syndrome is a movement disorder that causes uncomfortable sensations in the legs. These sensations typically are worse during periods of rest, especially just before sleeping at night, but they may happen during daytime periods of inactivity, such as watching a movie, attending a long business meeting, or flying in a plane.

The discomfort of restless legs syndrome usually is accompanied by an overwhelming urge to move the legs, which may relieve leg discomfort temporarily. At night, people with restless legs syndrome often find that their leg symptoms make it difficult to fall asleep. Because of this, insomnia is common, together with extreme drowsiness and fatigue during the daytime.

The cause of restless legs syndrome remains unknown. However, evidence suggests that there is a problem related to a brain chemical (neurotransmitter) called dopamine. Since restless legs syndrome may affect family members across generations, scientists suspect that there is some genetic (inherited) risk of the problem. In addition, genetic studies find an association between certain genes and restless legs syndrome. Still, a definite genetic cause has not been confirmed.

In some people with restless legs syndrome, anemia due to iron deficiency may be a contributing factor, while in others restless legs syndrome has been linked to pregnancy, diabetes, multiple sclerosis, rheumatoid arthritis, kidney failure, varicose veins or peripheral neuropathy (nerve damage in the hands and feet). High caffeine intake (coffee, tea, cola beverages, chocolate) and some vitamin deficiencies also may be related to restless legs syndrome.

Although restless legs syndrome tends to be more common and more severe in people over age 50, it can occur in men and women of any age group, even in young people who may be misdiagnosed as hyperactive. Currently, tens of thousands of people in the United States have restless legs syndrome that is severe enough to disrupt normal daily life. However, researchers estimate that even more people -- possibly up to 3% to 8% of the U.S. population -- may have occasional, milder symptoms of restless legs syndrome.


Restless legs syndrome causes a wide range of uncomfortable leg sensations, which may be described as any of the following: tingling, prickly, wormy, boring, crawling, pulling, drawing and, sometimes, pain. Although the muscles of the lower legs are affected most often, restless legs syndrome occasionally can cause symptoms in the arms as well. The discomfort of restless legs syndrome is almost always accompanied by an irresistible need to move the legs. Leg movement, such as walking, stretching and deep knee bends, seems to bring temporary relief. A leg massage or a warm bath also may help.

In addition to leg discomfort, restless legs syndrome also can cause periodic jerking leg movements during sleep. These involuntary leg movements often disturb both the patient and the patient's bed partner. Also, because symptoms of restless legs syndrome tend to be worse at bedtime, people with restless legs syndrome may find it hard to fall asleep and to stay asleep. This can cause insomnia and severe daytime drowsiness that may interfere significantly with work, school and social life.

Restless Legs Syndrome


Your doctor will diagnose restless legs syndrome based on your symptoms, medical history, family history and a physical examination. Your doctor also will do a neurological examination to look for nerve damage. He or she may order routine blood tests to check for anemia, iron or vitamin deficiency, diabetes and kidney problems. If the body's stores of iron are low, iron supplements may relieve the restless legs syndrome symptoms.

Many people with restless legs syndrome also have involuntary, periodic, jerking leg movements during sleep. The movements occur 1 to 10 times per minute. A sleep study can determine how much this is happening and how it is affecting your sleep. In some cases, an overnight sleep study at a sleep clinic may be necessary

Expected Duration

In women who first develop restless legs syndrome during pregnancy, symptoms often disappear after delivery. In other people with restless legs syndrome, the disorder may be a lifelong problem.


Although there is no way to prevent restless legs syndrome, it may help to avoid caffeine, alcohol and cigarette smoking.


Treatment of restless legs syndrome depends on the severity of your symptoms. If your symptoms are mild, simply exercising, stretching or massaging your legs, or taking a hot bath may bring relief. Lifestyle changes also may help, especially following a balanced diet and avoiding caffeine, alcohol and cigarette smoking. Iron treatment may be helpful, even when there is no evidence of iron deficiency.

Many experts also recommend mentally challenging activities, such as crossword puzzles or video games, to reduce symptoms (perhaps by distraction).

A number of medications, taken individually or in combination, may be effective to treat restless legs syndrome. These medications include:

Many people with restless legs syndrome also have periodic limb movement disorder (PLMD), a common movement disorder that causes involuntary, periodic, jerking leg movements during sleep. The movements occur 1 to 10 times per minute. The degree of periodic limb movement and how it affects sleep is best assessed with a sleep study (polysomnogram).

When To Call A Professional

Call your doctor whenever you have long-lasting, unexplained discomfort in any part of your body, especially if this discomfort prevents you from sleeping normally.


Symptoms of restless legs syndrome often become more severe with age, although the disorder tends to come and go. In some cases, avoiding caffeine or treatment with medications can dramatically decrease restless legs syndrome symptoms.

External resources

National Heart, Lung, and Blood Institute (NHLBI)
P.O. Box 30105
Bethesda, MD 20824-0105
Phone: (301) 592-8573
TTY: (240) 629-3255
Fax: (301) 592-8563

National Center on Sleep Disorders Research
National Institutes of Health
6705 Rockledge Drive
One Rockledge Centre, Suite 6022
Bethesda, MD 20892-7993
Phone: (301) 435-0199
Fax: (301) 480-3451

Restless Legs Syndrome (RLS) Foundation
819 Second St. SW
Rochester, MN 55902-2985
Phone: (507) 287-6465
Fax: (507) 287-6312
