Most primary RLS cases are idiopathic, which means that the cause is unknown.   In 50 percent of primary RLS cases, a family history of the condition can be detected, which would suggest the possibility of a genetics playing a role.   RLS symptoms tend to start at an earlier age and the condition progresses more slowly in those sufferers who have a family history of RLS.

Secondary RLS means that symptoms of restless leg syndrome accompany other conditions, such as kidney failure, diabetes, and Parkinson’s disease.   Unfortunately, there is no proof of a cause-and-effect relationship, but included below are some conditions and factors that seem to be related to RLS:

• Anemia (once low iron levels or anemia is corrected, RLS symptoms may be reduced)
• Chronic diseases, including kidney failure, diabetes, Parkinson’s disease and peripheral neuropathy (RLS symptoms may be reduced if the underlying condition is treated)
• Pregnancy, especially in the last trimester (symptoms will usually disappear in the last trimester)
• Anti-nausea drugs (prochlorperazine or metoclopramide), anti-seizure drugs (phenytoin or droperidol), anti-psychotic drugs (haloperidol or phenothiazine derivatives), and some cold and allergy medications may aggravate symptoms (consider talking with your doctor about changing your medications)
• Caffeine, alcohol or tobacco may trigger RLS symptoms (reduction or complete elimination of these may relieve symptoms)

A clinical diagnosis of restless leg syndrome is difficult to make because the doctor must rely on the patient’s description of symptoms, family history and current medications.   There is no lab test for RLS specifically; although lab tests will be done to rule out other conditions, including anemia, diabetes, and kidney disease.   Sleep studies may be done a well.

Your doctor may ask the following questions:

• Do you experience unpleasant or creepy, crawly sensations in your legs, associated with a strong urge to move?
• Does moving around help relieve these sensations?
• Are you more bothered by these sensations when sitting or at night?
• Do you often have trouble falling asleep or staying asleep?
• Have you been told that your legs or your arms jerk while you sleep?
• Does anyone else your family have restless legs?