What Causes Restless Legs Syndrome?

Faulty Use or Lack of Iron

Research suggests that restless legs syndrome (RLS) is mainly due to the faulty use or lack of iron in the brain. The brain uses iron to make the chemical dopamine and to control other brain activities. Dopamine works in the parts of the brain that control movement.

A number of conditions can affect how much iron is in the brain or how it’s used. These conditions include kidney failure, Parkinson disease, diabetes, rheumatoid arthritis, pregnancy, and iron deficiency. All of these conditions increase the risk of having RLS.

People whose family members have RLS also are more likely to develop the disorder. This suggests that genetics may contribute to the faulty use or lack of iron in the brain that triggers RLS.

Nerve Damage

Nerve damage in the legs or feet and sometimes in the arms or hands may cause or worsen RLS. Several conditions can cause such nerve damage, including diabetes.

Medicines and Substances

Certain medicines may trigger RLS. These include some:

• Antinausea medicines (used to treat upset stomach)
• Antidepressants (used to treat depression)
• Antipsychotics (used to treat certain mental health disorders)
• Cold and allergy medicines that contain antihistamines
• Calcium channel blockers (used to treat heart problems and high blood pressure)

RLS symptoms usually get better or may even go away if the medicine is stopped.

Certain substances, such as alcohol and tobacco, also can trigger or worsen RLS symptoms. Symptoms may get better or go away if the substances are stopped.