You might be watching a movie, sitting in an airplane, or lying in bed when the symptoms of restless legs come on. People have described the uncomfortable urge to move their legs as an achiness, an itch that can’t be scratched, as a throbbing or painful cramping or, more simply, as pain. It’s annoying, and for some people it can interfere with sleep, job performance, and relationships.

They might get relief when they move their legs, or get up and walk, but the urge could come back again.

“Restless legs certainly can lower the quality of your life,” says neurologist Brian Koo, MD, director of the Yale Medicine Program for Restless Legs Syndrome (RLS) and an internationally recognized RLS expert. “Luckily, even though we don’t know what causes restless legs, it’s very treatable,” Dr. Koo says.

RLS, also known as Willis Ekbom Disease (after the neurologist who first acknowledged it), is a sleep and movement disorder. Messages from the brain cause a feeling like an energy is building up in the legs, usually during sleep. You need to move or do something that will relieve the feeling. 

This can occur with just about any frequency or severity—it can happen a couple of times a year or several times a night. In extreme cases, restless legs can happen anytime, even during a during a conversation with a friend or at a work meeting. People have reported the same feeling of restlessness in their arms, face, torso, and genitals, although these are rare compared to symptoms in the legs.

Up to 7 to 10 percent of the U.S. population might have restless legs. While RLS affects people of all ages, the condition is more prevalent and serious in people who are middle-aged or older, and women are affected twice as often as men. 

While there is no known cause for RLS, in some cases it is associated with anemia or pregnancy (although it usually disappears around the time the baby is born). While it often runs in families—and there are gene variants linked to RLS—it also occurs more frequently in people with iron deficiency and renal failure.

One of the most frustrating side effects of RLS is loss of sleep. Dr. Koo says two-thirds of people who have RLS take at least 30 minutes to fall asleep at night, and a quarter take an hour or more to fall asleep. (About 15 to 20 minutes is considered to be a normal amount of time to fall asleep.) This, in turn, can lead to daytime sleepiness and exhaustion, and even problems with memory and concentration.

“Restless legs can be progressive, but that doesn’t mean it will be,” says Dr. Koo. While symptoms never stop completely, they can disappear for days and even months.

The majority of people who have restless legs syndrome often have abnormal movements known as periodic limb movements during sleep. This causes their legs and sometimes their arms to twitch during sleep, usually every 15 to 40 seconds, sometimes hundreds of times a night. Studies have linked periodic limb movements in sleep to an increased risk for heart problems.

Your doctor will consider RLS if you report an urge to move your legs when you are resting or inactive, and if the urge is relieved, at least partially, by movement. The doctor will want to know if the urge and any unpleasant sensations that accompany it are worse or occur only at night.

Your doctor will want to talk about possible lifestyle changes, as minimizing alcohol, caffeine, and tobacco consumption can alleviate symptoms. Medications may also be contributing to the problem. This includes common medications you may be taking for allergies, colds, depression, and nausea. “Some people might be taking Benadryl to help them fall asleep, but it’s making restless legs worse,” Dr. Koo says.

The next step will be to check your iron levels, since low iron can be a factor in RLS. In some cases, a doctor will recommend an overnight stay in a sleep study laboratory to rule out sleep apnea as the two conditions often co-exist, and sleep apnea, when left untreated, can aggravate RLS.

RLS is believed to be underdiagnosed. This is partly because there is no single test that can be used to diagnose it, and it can be confusing because other conditions can mimic restless legs syndrome, including leg cramps or a neuropathy, which is a disease or dysfunction in a peripheral nerve.

There is no cure for RLS, but most people can control the symptoms with help. First, your doctor will want to make sure you have eliminated alcohol, caffeine, and tobacco. He or she will suggest lifestyle changes, including developing a regular sleep routine, and trying moderate exercise and relaxation techniques. Baths, massaging the legs, and applying hot and cold packs can help, too.

“If we ask them all these questions and their restless legs are still getting worse, we will consider medication,” says Dr. Koo. Medications known as dopamine agonists, also used to treat Parkinson’s disease, can help people with RLS. If you have a severe case that does not respond to these medications or other treatments, your doctor may prescribe opioids, since they often help with RLS.

Medications that help with sleep may not help with restless leg syndrome, Dr. Koo adds.

The Yale Medicine Restless Legs Syndrome Program is dedicated to recognizing, evaluating, treating, and understanding RLS. 

The program consists of specialists from neurology, sleep medicine, radiology, and psychiatry. In addition, to expertise in RLS, practitioners in the program have expertise in the assessment and treatment of sleep-disordered breathing, depression, and insomnia, conditions that can occur along with RLS. Our doctors use such tools as polysomnography (a study that records leg movements and assesses breathing during sleep), neuroimaging, and an infusion center for patients who need intravenous iron.

In addition, Yale Medicine is interested in developing a better understanding of RLS and optimizing treatment strategies through ongoing clinical trials.