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 seven 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.
Few data are available about the prevalence of RLS in racial groups. However, it has been suggested that the Black American population is at lower risk than the white population.
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:
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 a 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:
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.
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.
In most cases, the cause of 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:
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.
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 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.
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:
The following lifestyle changes and activities may provide some relief if you have mild to moderate RLS:
