A person with restless legs syndrome experiences twitchiness and discomfort in the legs, usually after going to bed. As this can lead to insomnia, it is considered a sleep disorder.

Restless legs syndrome (RLS) may happen because of mental or physical problems, or it may be an adverse effect of some medications. It is also known as Willis-Ekbom disease.

Restless legs syndrome may be classed as mild or severe, depending on the frequency and severity of the symptoms, how well the symptoms can be relieved by moving around, and how much disturbance they cause.

It affects up to 1 in 10 people at some time during their life.

The vast majority of cases of RLS resolve on their own over time or once simple lifestyle changes have been made.

What causes restless legs syndrome (RLS)?

Restless legs syndrome (RLS) has been found to be a genetic syndrome in some cases, meaning that parents with RLS can pass it down to their children. Up to 92% of patients with RLS have a first-degree relative with the disorder. These patients tend to develop symptoms earlier in life (before age 45) than those with RLS without the genetic link.

In addition to the genetic source, many medical problems are closely associated with the development of RLS, including:

• Low levels of iron (iron deficiency).
• Uremia (a condition associated with worsening kidney function).
• Hypothyroidism.
• Depression.
• Fibromyalgia.
• Parkinson’s disease.
• Kidney disease.
• Diabetes.
• Rheumatoid arthritis.
• Peripheral neuropathy.
• Pregnancy.
• Dialysis.

Medications can also contribute to the development of RLS. Such known medications include antidepressants, allergy drugs and anti-nausea medications. Caffeine, nicotine and alcohol can also make symptoms worse.

What are the symptoms of restless legs syndrome (RLS)?

Symptoms of restless legs syndrome include:

• Leg (or arm) discomfort: These uncomfortable limb sensations are often described by adults as creeping, itching, pulling, crawling, tugging, throbbing, burning, or gnawing. These sensations usually occur at bedtime but can occur at other times of limb inactivity.
• Urge to move legs (or arms): To relieve limb discomfort, you have an uncontrollable urge to move your limbs especially when resting, such as when sitting or lying down.
• Sleep disruption: Additional time is often needed to fall asleep because of the urge to move your limbs to relieve the discomfort. Sometimes staying asleep may also be difficult.
• Bedtime behavior problems: Because of the discomfort, you may need to get out of bed to stretch your limbs to relieve the discomfort.
• Daytime sleepiness: Problems with falling asleep and staying asleep may result in daytime sleepiness.
• Behavior and work performance problems: Again, due to sleep disruption, problems may emerge in daytime behavior (irritability, moodiness, difficulty concentrating, hyperactivity, etc) and work performance.

How is restless legs syndrome diagnosed?

Since there is no specific test for RLS, the condition is diagnosed by a doctor’s evaluation.  The five basic criteria for clinically diagnosing the disorder are:

• A strong and often overwhelming need or urge to move the legs that is often associated with abnormal, unpleasant, or uncomfortable sensations.
• The urge to move the legs starts or get worse during rest or inactivity.
• The urge to move the legs is at least temporarily and partially or totally relieved by movements. 
• The urge to move the 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 physician will focus largely on the individual’s descriptions of symptoms, their triggers and relieving factors, as well as the presence or absence of symptoms throughout the day.  A neurological and physical exam, plus information from the person’s medical and family history and list of current medications, may be helpful.  Individuals may be asked about frequency, duration, and intensity of symptoms; if movement helps to relieve symptoms; 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.  Laboratory tests may rule out other conditions such as kidney failure, iron deficiency anemia (which is a separate condition related to iron deficiency), or pregnancy that may be causing symptoms of RLS.  Blood tests can identify iron deficiencies as well as other medical disorders associated with RLS.  In some cases, sleep studies such as polysomnography (a test that records the individual’s brain waves, heartbeat, breathing, and leg movements during an entire night) may identify the presence of other causes of sleep disruption (e.g., sleep apnea), which may impact management of the disorder.  Periodic limb movement of sleep during a sleep study can support the diagnosis of RLS but, again, is not exclusively seen in individuals with RLS.

Diagnosing RLS in children may be especially difficult, since it may be hard for children to describe what they are experiencing, when and how often the symptoms occur, and how long symptoms last.  Pediatric RLS can sometimes be misdiagnosed as “growing pains” or attention deficit disorder.

How is restless legs syndrome treated?

RLS can be treated, with care directed toward relieving symptoms.  Moving the affected limb(s) may provide temporary relief.  Sometimes RLS symptoms can be controlled by finding and treating an associated medical condition, such as peripheral neuropathy, diabetes, or iron deficiency anemia.

Iron supplementation or medications are usually helpful but no single medication effectively manages RLS for all individuals.  Trials of different drugs may be necessary.  In addition, medications taken regularly may lose their effect over time or even make the condition worse, making it necessary to change medications.

Treatment options for RLS include:

 Lifestyle changes.  Certain lifestyle changes and activities may provide some relief in persons with mild to moderate symptoms of RLS.  These steps include avoiding or decreasing the use of alcohol and tobacco, changing or maintaining a regular sleep pattern, a program of moderate exercise, and massaging the legs, taking a warm bath, or using a heating pad or ice pack.  There are new medical devices that have been cleared by the U.S. Food & Drug Administration (FDA), including a foot wrap that puts pressure underneath the foot and another that is a pad that delivers vibration to the back of the legs.  Aerobic and leg-stretching exercises of moderate intensity also may provide some relief from mild symptoms.

Iron.  For individuals with low or low-normal blood tests called ferritin and transferrin saturation, a trial of iron supplements is recommended as the first treatment.  Iron supplements are available over-the-counter.  A common side effect is upset stomach, which may improve with use of a different type of iron supplement.  Because iron is not well-absorbed into the body by the gut, it may cause constipation that can be treated with a stool softeners such as polyethylene glycol.  In some people, iron supplementation does not improve a person’s iron levels.  Others may require iron given through an IV line in order to boost the iron levels and relieve symptoms.

Anti-seizure drugs.  Anti-seizure drugs are becoming the first-line prescription drugs for those with RLS.  The FDA has approved gabapentin enacarbil for the treatment of moderate to severe RLS, This drug appears to be as effective as dopaminergic treatment (discussed below) and, at least to date, there have been no reports of problems with a progressive worsening of symptoms due to medication (called augmentation).  Other medications may be prescribed “off-label” to relieve some of the symptoms of the disorder.

Other anti-seizure drugs such as the standard form of gabapentin and pregabalin can decrease such sensory disturbances as creeping and crawling as well as nerve pain.  Dizziness, fatigue, and sleepiness are among the possible side effects.  Recent studies have shown that pregabalin is as effective for RLS treatment as the dopaminergic drug pramipexole, suggesting this class of drug offers equivalent benefits.

Dopaminergic agents.  These drugs, which increase dopamine effect, are largely used to treat Parkinson’s disease.  They have been shown to reduce symptoms of RLS when they are taken at nighttime.  The FDA has approved ropinirole, pramipexole, and rotigotine to treat moderate to severe RLS.  These drugs are generally well tolerated but can cause nausea, dizziness, or other short-term side effects.  Levodopa plus carbidopa may be effective when used intermittently, but not daily.

Although dopamine-related medications are effective in managing RLS symptoms, long-term use can lead to worsening of the symptoms in many individuals.  With chronic use, a person may begin to experience symptoms earlier in the evening or even earlier until the symptoms are present around the clock.  Over time, the initial evening or bedtime dose can become less effective, the symptoms at night become more intense, and symptoms could begin to affect the arms or trunk.  Fortunately, this apparent progression can be reversed by removing the person from all dopamine-related medications. 

Another important adverse effect of dopamine medications that occurs in some people is the development of impulsive or obsessive behaviors such as obsessive gambling or shopping.  Should they occur, these behaviors can be improved or reversed by stopping the medication.

Opioids.  Drugs such as methadone, codeine, hydrocodone, or oxycodone are sometimes prescribed to treat individuals with more severe symptoms of RLS who did not respond well to other medications.  Side effects include constipation, dizziness, nausea, exacerbation of sleep apnea, and the risk of addiction; however, very low doses are often effective in controlling symptoms of RLS.

Benzodiazepines.  These drugs can help individuals obtain a more restful sleep.  However, even if taken only at bedtime they can sometimes cause daytime sleepiness, reduce energy, and affect concentration.  Benzodiazepines such as clonazepam and lorazepam are generally prescribed to treat anxiety, muscle spasms, and insomnia.  Because these drugs also may induce or aggravate sleep apnea in some cases, they should not be used in people with this condition.  These are last-line drugs due to their side effects.

You and your doctor will discuss the treatment that might be best for you.