Introduction

Restless legs syndrome, also known as Willis-Ekbom disease, is a common condition of the nervous system that causes an overwhelming, irresistible urge to move the legs.

It can also cause an unpleasant crawling or creeping sensation in the feet, calves and thighs. The sensation is often worse in the evening or at night. Occasionally, the arms are affected too.

Restless legs syndrome is also associated with involuntary jerking of the legs and arms, known as periodic limb movements in sleep (PLMS).

Some people have the symptoms of restless legs syndrome occasionally, while others have them every day. The symptoms can vary from mild to severe. In severe cases, restless legs syndrome can be very distressing and disrupt a person's daily activities.

What causes restless legs syndrome?

In the majority of cases, there's no obvious cause of restless legs syndrome. This known as idiopathic or primary restless legs syndrome, and it can run in families.

Some neurologists (specialists in treating conditions that affect the nervous system) believe the symptoms of restless legs syndrome may have something to do with how the body handles a chemical called dopamine. Dopamine is involved in controlling muscle movement and may be responsible for the involuntary leg movements associated with restless legs syndrome.

In some cases, restless legs syndrome is caused by an underlying health condition, such as iron deficiency anaemia or kidney failure. This is known as secondary restless legs syndrome.

There's also a link between restless legs syndrome and pregnancy. About 1 in 5 pregnant women will experience symptoms in the last three months of their pregnancy, although it's not clear exactly why this is. In such cases, restless legs syndrome usually disappears after the woman has given birth.

Read more about the causes of restless legs syndrome

Treating restless legs syndrome

Mild cases of restless legs syndrome that aren't linked to an underlying health condition may not require any treatment, other than making a few lifestyle changes, such as:

  • adopting good sleep habits – for example, following a regular bedtime ritual, sleeping regular hours, and avoiding alcohol and caffeine late at night
  • quitting smoking if you smoke
  • exercising regularly during the daytime

If your symptoms are more severe, you may need medication to regulate the levels of dopamine and iron in your body.

If restless legs syndrome is caused by iron deficiency anaemia, iron supplements may be all that's needed to treat the symptoms.

Read more about treating restless legs syndrome

Who's affected by restless legs syndrome?

As many as 1 in 10 people are affected by restless legs syndrome at some point in their life.

Women are twice as likely to develop restless legs syndrome than men. It's also more common in middle age, although the symptoms can develop at any age, including childhood.

Outlook

The symptoms of restless legs syndrome will usually disappear if it's possible to address an underlying cause. 

However, if the cause is unknown, the symptoms can sometimes get worse with time and severely affect the person's life. Restless legs syndrome isn't life threatening, but severe cases can severely disrupt sleep (causing insomnia) and trigger anxiety and depression.

Symptoms

Restless legs syndrome typically causes an overwhelming urge to move your legs and an uncomfortable sensation in your legs.

The sensation may also affect your arms, chest and face, too. It has been described as:

  • tingling, burning, itching or throbbing
  • a "creepy-crawly" feeling
  • feeling like fizzy water is inside the blood vessels in the legs
  • a painful, cramping sensation in the legs, particularly in the calves 

These unpleasant sensations can range from mild to unbearable, and are usually worse in the evening and during the night. They can often be relieved by moving or rubbing your legs.

Some people experience symptoms occasionally, while others have them every day. You may find it difficult to sit for long periods of time – for example, on a long train journey.

Just over half of people with restless legs syndrome also experience episodes of lower back pain.

Periodic limb movements in sleep (PLMS)

Up to 80% of people with restless legs syndrome also have periodic limb movements in sleep (PLMS).

If you have PLMS, your leg will jerk or twitch uncontrollably, usually at night while you're asleep. The movements are brief and repetitive, and usually occur every 10 to 60 seconds.

PLMS can be severe enough to wake up both you and your partner. The involuntary leg movements can also occur when you're awake and resting.

Causes

In many cases, the exact cause of restless legs syndrome is unknown.

When no cause can be found, it's known as "idiopathic" or primary restless legs syndrome.

Research has identified specific genes related to restless legs syndrome, and it can run in families. In these cases, symptoms usually occur before the age of 40.

Dopamine

There's evidence to suggest restless legs syndrome is related to a problem with part of the brain called the basal ganglia. The basal ganglia uses a chemical (neurotransmitter) called dopamine to help control muscle activity and movement.

Dopamine acts as a messenger between the brain and nervous system to help the brain regulate and co-ordinate movement. If nerve cells become damaged, the amount of dopamine in the brain is reduced, which causes muscle spasms and involuntary movements.

Dopamine levels naturally fall towards the end of the day, which may explain why the symptoms of restless legs syndrome are often worse in the evening and during the night.

Underlying health condition

Restless legs syndrome can sometimes occur as a complication of another health condition, or it can be the result of another health-related factor. This is known as secondary restless legs syndrome.

You can develop secondary restless legs syndrome if you:

Triggers

There are a number of triggers that don't cause restless legs syndrome, but can make symptoms worse. These include medications such as:

Other possible triggers include:

Diagnosis

There's no single test for diagnosing restless legs syndrome.

A diagnosis will be based on your symptoms, your medical and family history, a physical examination, and your test results.

Your GP should be able to diagnose restless legs syndrome, but they may refer you to a neurologist if there's any uncertainty.

There are four main criteria your GP or specialist will look for to confirm a diagnosis. These are:

  • an overwhelming urge to move your legs, usually with an uncomfortable sensation such as itching or tingling
  • your symptoms occur or get worse when you're resting or inactive
  • your symptoms are relieved by moving your legs or rubbing them
  • your symptoms are worse during the evening or at night

Assessing your symptoms

Your GP or specialist will ask you about the pattern of your symptoms to help assess their severity. For example, they may ask you:

  • how often you have symptoms
  • how unpleasant you find your symptoms
  • whether your symptoms cause significant distress
  • whether your sleep is disrupted, making you tired during the day

Keeping a sleep diary may help your doctor assess your symptoms. You can use the diary to record your daily sleeping habits, such as the time you go to bed, how long it takes you to fall asleep, how often you wake during the night, and episodes of tiredness during the day.

Mild symptoms of restless legs syndrome can usually be treated by making lifestyle changes – for example, establishing a regular sleeping pattern and avoiding stimulants, such as caffeine, alcohol or tobacco, in the evening.

If your symptoms are more severe, you may need medication to bring them under control.

Read more about treating restless leg syndrome

Blood tests

Your GP may refer you for blood tests to confirm or rule out possible underlying causes of restless legs syndrome. For example, you may have blood tests to rule out conditions such as anaemiadiabetes and kidney function problems.

It's particularly important to find out the levels of iron in your blood because low iron levels can sometimes cause secondary restless legs syndrome. Low iron levels can be treated with iron tablets.

Sleep tests

If you have restless legs syndrome and your sleep is being severely disrupted, sleep tests – such as a suggested immobilisation test – may be recommended. The test involves lying on a bed for a set period of time without moving your legs while any involuntary leg movements are monitored.

Occasionally, polysomnography may be recommended. This is a test that measures your breathing rate, brain waves and heartbeat throughout the course of a night. The results will confirm whether you have periodic limb movements in sleep (PLMS).

Treatment

Mild restless legs syndrome that isn't linked to an underlying health condition can be managed with just a few lifestyle changes.

If symptoms are more severe, medication may be needed.

Restless legs syndrome caused by an underlying health condition can often be cured by treating that condition. For example, iron deficiency anaemia can be treated by taking iron supplements.

If it's associated with pregnancy, it usually disappears on its own within four weeks of the birth.

Lifestyle changes

A number of lifestyle changes may be enough to ease the symptoms of restless legs syndrome, including:

  • avoiding stimulants in the evening – such as caffeine, tobacco and alcohol
  • not smoking – read more about quitting smoking
  • taking regular daily exercise – but avoid exercising near bedtime
  • practising good sleep habits – for example, going to bed and getting up at the same time every day, not napping during the day, taking time to relax before going to bed, and avoiding caffeine close to bedtime
  • avoiding medicines that trigger the symptoms or make them worse – if you think medication is causing your symptoms, continue to take it and make an appointment to see your GP

During an episode of restless legs syndrome, the following measures may help relieve your symptoms:

  • massaging your legs
  • taking a hot bath in the evening
  • applying a hot or cold compress to your leg muscles
  • doing activities that distract your mind, such as reading or watching television
  • relaxation exercises, such as yoga or tai chi
  • walking and stretching

A small medical trial carried out in 2011 found a type of osteopathic exercise technique called positional release manipulation could be of benefit to people with restless legs syndrome. It involves holding different parts of the body in positions found to reduce feelings of pain and discomfort.

Medication

Dopamine agonists

Dopamine agonists may be recommended if you're experiencing frequent symptoms of restless legs syndrome. They work by increasing dopamine levels, which are often low.

Dopamine agonists that may be recommended include:

  • ropinirole 
  • pramipexole 
  • rotigotine skin patch

These medications can occasionally make you feel sleepy, so you should be cautious when driving or using tools or machinery after taking them. Other possible side effects can include nausea, dizziness and headaches.

If you experience nausea while taking a dopamine agonist, you may be given medication to help with this (antiemitic medication).

Impulse control disorder (ICD) is a less common side effect sometimes associated with dopamine agonists.

People with ICD are unable to resist the urge to do something harmful to themselves or others. For example, this could be an addiciton to alcohol, drugs, gambling, shopping, or sex (hypersexuality).

However, the urges associated with ICD will subside once treatment with the dopamine agonist is stopped.

Painkillers

A mild opiate-based painkiller, such as codeine or tramadol, may be prescribed to relieve pain associated with restless legs syndrome.

Gabapentin and pregabalin are also sometimes prescribed to help relieve painful symptoms of restless legs syndrome. Side effects of these medications include dizziness, tiredness and headaches.

Aiding sleep

If restless legs syndrome is disrupting your sleep, a short-term course of medication may be recommended to help you sleep.

These types of medication are known as hypnotics, and include temazepam and loprazolam. Hypnotics are usually only recommended for short-term use (typically no longer than a week).

You may find you still feel sleepy or "hungover" the morning after taking your medication. 

Levodopa

Levodopa may be recommended if you only have occasional symptoms of restless legs syndrome. This is because if you took levodopa every day, there's a high risk it would actually make your symptoms worse.

Levodopa is available in tablet or liquid form, and you should take it once you feel the symptoms of restless legs syndrome coming on.

The medication will make you feel very sleepy (often suddenly), so you should never drive or use tools or machinery after taking levodopa.