Restless legs syndrome, or RLS, causes an irresistible urge to move the legs, usually while lying down or trying to fall asleep. It is more common among people with multiple sclerosis (MS). Nerve damage may help explain the connection between RLS and MS.

According to estimates, 5–15% of people in the United States live with RLS, which doctors may also call Willis-Ekbom disease. RLS seems to be more prevalent among people with MS, suggesting that there is a link between these conditions.

The two conditions also have some symptoms in common. For instance, RLS can affect sleep and mood. Sleep disorders and mood changes, such as depression, are also among the common symptoms of MS.

Keep reading to learn more about the link between RLS and MS, including the causes, symptoms, and treatment of these conditions.

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RLS is a common movement disorder that causes intense discomfort in the legs, usually when a person is lying down or trying to sleep.

A person with this condition may feel an overwhelming need to move their legs. This can make it very difficult or even painful to sleep.

People with RLS describe having sensations of burning, itching, tickling, or creeping and crawling. The longer they resist moving their legs, the more intense the need to move them becomes.

RLS can contribute to insomnia and daytime fatigue. Some people may also develop depression or anxiety.

Learn more about RLS.

Several studies have found significantly higher rates of RLS among people with MS than among the general population.

In a 2021 study involving 236 people, the prevalence of RLS was seven times higher — 23.9% compared with 3.4% — among people with MS than in the control group. The results also indicate that RLS has a link to increased sleep difficulties and daytime sleepiness.

Research from 2018 arrived at a similar conclusion, finding a pooled rate of RLS of 26% among people living with MS. This rate was lower in Asia, where the prevalence of RLS was 20%. The researchers also found that the rate of RLS differed among sexes, with the condition affecting 26% of females compared with 17% of males.

Both studies found higher rates of MS-related disability among people with RLS.

A 2018 study reported lower sleep quality, increased fatigue and depression, and reduced health-related quality of life among people with both MS and RLS. These findings indicate that treating RLS effectively may improve the lives of people with MS.

Doctors do not fully understand the link between RLS and MS.

The authors of a 2021 study note that no recent studies have tested and controlled for potential variables that can explain the differences. For instance, the data cannot explain why both RLS and MS are more common among females.

The study found that certain factors increase the risk of RLS in people with MS. These factors include:

  • being female
  • having more disease symptoms
  • having a higher disability score
  • having MS spinal lesions

Additionally, some people with MS may experience mood issues, such as depression. As a result, they may take antidepressant medications that can increase their risk of RLS.

Further research is necessary to uncover the link between RLS and MS.

There is evidence to suggest that genetics, dysfunction in the brain’s dopamine system, and low iron in the brain may cause RLS.

There are two forms of RLS: primary and secondary. In people with primary RLS, the syndrome occurs on its own and is not the result of some other disease. Conversely, in those with secondary RLS, the symptoms develop as a result of pregnancy or another medical condition, such as:

These conditions are not risk factors for MS and do not occur as a result of the disease.

People with MS may develop peripheral neuropathy, which is a type of nerve pain. Neurological symptoms are also common among people with RLS. Given that researchers have found an increased risk of RLS in people who have more disabling MS, this might mean that progressive nerve damage plays a role in RLS.

MS is a chronic autoimmune disease. As with other autoimmune disorders, it causes the immune system to attack healthy parts of the body.

People with MS develop inflammation in the central nervous system (CNS). The body attacks myelin, which is the substance that coats neurons.

Over time, a person may develop lesions in their CNS and lose neurons, which can affect many aspects of health and functioning. A person may experience a range of symptoms, such as:

  • nerve damage and nerve pain
  • movement difficulties
  • balance problems
  • loss of bladder or bowel control
  • sleep difficulties
  • depression or anxiety
  • brain fog and difficulties concentrating
  • vision problems
  • shaking and tremors
  • numbness
  • weakness or paralysis in parts of the body

There is no cure for MS, and it may get worse with time. However, a number of treatments, including a group of drugs called disease-modifying therapies (DMTs), may ease the symptoms and slow the progression of the disease. DMTs may also help the disease go into remission, meaning that a person experiences few or no symptoms.

Learn about how doctors diagnose MS.

Research has shown that the risk of RLS in MS increases with the presence of MS spinal lesions and increased physical disability. It has also indicated that RLS symptoms persist despite the use of DMTs.

This suggests that the severity of MS correlates with RLS risk but that treating MS may not treat RLS. Certain lifestyle adjustments and supportive strategies may improve symptoms of RLS in people with MLS. A person can try:

  • limiting caffeine, especially in the hours leading up to bedtime
  • avoiding drugs that reduce dopamine levels — including certain antidepressants, antipsychotic drugs, anti-nausea drugs, and antihistamines — if a doctor says that this is possible
  • asking for an iron test and taking iron supplements if necessary
  • massaging restless legs
  • applying a heating pad to the legs
  • exercising during the day
  • asking a doctor about a folate or magnesium supplement

If these strategies are ineffective, a doctor may be able to prescribe medications. For the treatment of RLS, the Food and Drug Administration (FDA) has approved the following:

  • rotigotine (Neupro)
  • pramipexole (Mirapex)
  • ropinirole (Requip)
  • gabapentin enacarbil (Horizant)

Restless legs syndrome may be frustrating for people with multiple sclerosis, who might already experience chronic pain and sleep difficulties. Although RLS is not a symptom of MS, it affects about one-quarter of people with MS.

Various lifestyle adjustments can help relieve the symptoms, and medication is available should these prove ineffective. However, there is a lack of evidence to support the use of MS DMTs to treat RLS.

People who experience RLS should discuss the treatment options with a doctor and consider seeking support until they find a treatment that helps.