Restless legs syndrome in arms: Causes and treatment

What is RLS in the arms?

RLS is a neurological condition, also known as Willis-Ekbom disease.

While it primarily affects the legs, a 2019 review mentions research that suggests 21% to 57% of people with RLS may also experience symptoms in the arms. In these people, symptoms usually begin in the legs and affect the lower limbs more severely than the upper limbs.

However, in restless arms syndrome (RAS), the symptoms predominantly affect the arms. Although RLS is one of the most common neurological disorders, scientists believe RAS may be extremely rare due to a lack of reports.

That being said, doctors may also underdiagnose RAS due to its atypical presentation. Because of this, it is difficult to estimate the true prevalence of RAS.

Symptoms of RLS and RAS

The symptoms of RLS that affects the arms can vary from mild to severe.

Symptoms may affect one or both arms and include uncomfortable sensations, such as:

• burning
• aching
• pain
• itching
• tingling
• electric shock sensations
• restlessness
• general discomfort
• an urge to move the arms

The symptoms may occur or worsen at night or during rest. They may improve with movement.

Severe RLS or RAS may cause sleep disturbances, which may lead to reduced quality of life and mental health conditions, such as depression.

Causes and risk factors

RAS shares many of the same clinical characteristics as RLS. However, while there is evidence RLS can have primary or secondary causes, a 2021 review found no evidence of secondary RAS.

“Primary” means a condition occurs on its own, while “secondary” means it is the result of another condition.

This means it is unclear exactly what causes RAS. The causes of RLS that also affects the arms are better understood.

Primary RLS or RAS

Primary RAS or RLS occurs on its own, for no other reasons. Scientists are still learning why this happens. However, the condition may stem from:

• Genetics: People who have close relatives with RLS have a higher risk of developing the condition. This could also be true for RAS.
• Dopamine regulation: Dopamine is a neurotransmitter that affects various bodily functions, including movement, sleep, and mood. If the dopamine receptors in the brain do not regulate dopamine levels effectively, RLS or RAS symptoms may occur.

Secondary RLS

RLS in the arms could also be the result of another medical condition or a drug, such as:

• Iron deficiency: Iron helps the enzyme tyrosine hydroxylase synthesize dopamine. This means that low iron levels can affect how the body processes dopamine.
• Kidney insufficiency: RLS is two to three times more common in people with chronic kidney disease (CKD) than the larger population. Although scientists do not fully understand this link, they believe inflammation and iron deficiency may play a role.
• Diabetes: Individuals with diabetes may be at greater risk of iron deficiency and kidney disease, which could lead to RLS.
• Thyroid dysfunction: Scientists believe that an imbalance between thyroid hormones and dopamine activity in the brain may contribute to RLS.
• Medication: Various medications may increase a person’s risk of RLS, including:
  • antipsychotic drugs
  • some antidepressants
  • allergy and cold medications that contain older antihistamines
  • anti-nausea drugs
  • anesthetics

Diagnosis

Doctors may rely on a person’s description of their symptoms to diagnose RLS or RAS. The following must apply for a person to receive a diagnosis:

• an urge to move the arms or legs that starts or worsens during periods of rest and at night, usually accompanied by an unpleasant sensation
• movement partially or fully relieves the symptoms
• another medical or behavioral condition does not solely account for the symptoms

A doctor may perform tests, such as blood tests and urinalysis, to rule out other potential causes of symptoms.

Treatment for RAS

The treatment for RAS may depend on the severity of the condition.

For mild symptoms, a doctor may advise lifestyle adjustments and other nondrug treatments, such as:

• reducing caffeine and alcohol intake
• stopping smoking, if applicable
• implementing sleep hygiene
• engaging in regular physical activity
• getting massages
• practicing yoga
• using pneumatic compression devices

For severe symptoms, a doctor may prescribe medications such as:

• dopaminergic drugs, such as pramipexole and levodopa
• alpha-2 delta calcium channel 2 ligand drugs, such as gabapentin and pregabalin

If a medication is the cause of the symptoms, a doctor may suggest stopping the medication or switching to a different type, if possible. A person should not stop taking any medication without first consulting their doctor.

FAQ

How common is RAS?

There are few reported cases of RAS, which could indicate that the condition is extremely rare. However, the condition is likely underdiagnosed, which means the true prevalence is unknown.

RLS that affects both the arms and legs is more common.

Can pregnancy trigger RAS?

Around 1 in 5 pregnant people experience RLS, which shares clinical characteristics with RAS, during the final 3 months of pregnancy. RLS can affect the arms.

Can doctors cure RAS?

Because true RAS is rare, there is currently a lack of research into treatments. However, doctors can sometimes cure secondary RLS by treating the underlying cause of the condition.

Summary

Restless leg syndrome (RLS) can affect the arms as well as the legs. Rarely, people can have restless arms syndrome (RAS), which only affects the arms.

A person with either condition experiences uncomfortable sensations in the limbs and an urge to move them, particularly at night.

Treatment may depend on the severity of the condition. For some, lifestyle changes and self-care practices may be enough to reduce the symptoms. For others, medication may be necessary to improve sleep or quality of life.

It is best for anyone with symptoms of RLS or RAS to speak with a doctor, who can investigate whether there is an underlying cause.