Causes and Diagnoses

Causes and Diagnosis for Restless Legs Syndrome

The cause of restless legs syndrome (RLS) varies from person to person. In some cases, the cause is unknown, and sometimes it can be caused or made worse by other health issues or medication. These can include:

Iron deficiency

Low iron levels (deficiency) can cause problems with brain cell communication that can lead to restless legs syndrome. If you think you have RLS caused by low iron, talk with your physician and do not attempt to take supplements on your own.


This lifelong condition can damage blood vessels and nerves that affect leg muscles, causing restless legs syndrome. By properly managing your diabetes, you may help prevent or improve your RLS.


Many women have RLS when they are pregnant. It usually goes away within a month of giving birth.


Some medications can cause restless legs syndrome or make it worse:

  • Allergy medications
  • Many antidepressants
  • Antihistamines and over-the-counter sleep aids
  • Nearly all centrally active dopamine-receptor antagonists, including anti-nausea medications

Other possible causes for RLS may include kidney failure and peripheral neuropathy.

Diagnosing RLS


  • Do you have difficulty falling asleep because you have an urge to move your legs?
  • Do you wake up at night because you feel like your legs are on fire?
  • Do you feel an itching in your legs when you lie down to go to sleep?
  • Do your legs seem to feel better when you walk, stretch or make other movements?

If you answered yes to any of these questions, you may have restless legs syndrome. Talk to your physician if you think you have restless leg syndrome. Your physician will ask you about your medical history and if you are on any medications.

Your physician may also ask you to keep a sleep diary for two weeks to show when you sleep and for how long. You may also rate your how sleep is affecting your daily life using the Epworth Sleepiness Scale. Be sure to tell your physician if you or a relative have ever had a sleep disorder.

Your physician may also order blood tests, including measuring your iron. In some cases, a sleep study may be recommended. This is helpful, but is not required to diagnose restless legs syndrome.