The medical community's recognition of restless legs syndrome (RLS) has evolved over the past few decades. For years, patients complained to their doctors that they experienced a very uncomfortable and distressing feeling in their legs in the evening when they tried to rest, and eventually their doctors considered RLS to be a disorder.

RLS often interferes with the ability to fall asleep easily. Usually, patients do not describe it as painful, but more like a "creepy-crawly" sensation that creates a strong and irresistible urge to move the legs. Moving does help, but only for brief moments. Once people suffering with RLS fall asleep, they tend to have involuntary leg kicks.

The cause of RLS is not completely understood; however, it is thought to be associated with the function of dopamine, a nervous system neurotransmitter. Long ago, it was recognized that people with anemia were more likely to develop RLS, which makes sense because iron plays a role in how dopamine operates in the brain. When patients come in with RLS, we check their blood levels of iron and ferritin, which represent the body's capacity to store iron.

Pregnancy also may cause RLS, but usually the symptoms improve after the baby is delivered. However, some women who have had several children eventually have persistent RLS. Patients with some kidney diseases are more likely to develop RLS, and it can be caused by the use of some medications, especially antidepressants and antipsychotics. It does tend to run in families.

A variety of medications have been prescribed to try to help RLS patients. For many years, sleep specialists have prescribed medications that enhance dopamine functioning in the brain. These dopamine agonists already were available for the treatment of Parkinson disease, which, for very different reasons, is also associated with abnormalities in brain dopamine activity.

Some of the pharmaceutical companies that made these medications did the required research studies to gain official FDA approval for the treatment of RLS. Now there is more awareness among the public and medical professionals about RLS, due to medication advertising and other media attention.

A common question about RLS is whether it is really an actual condition. Certain comedians recently have made fun of the disorder's name and have suggested that it is simply made up. Some people skeptical of the pharmaceutical industry believe that RLS was defined as a disorder just to sell pills. Obviously, none of them suffer with RLS or have family members with the disorder. Researchers are making steady progress in understanding the underlying causes of RLS.

Health care professionals should check to see whether their patients have RLS. One question is enough to see whether they might have it. A "no" answer rules it out. A "yes" answer should lead to further evaluation. Here's the question: "When you try to relax in the evening, or go to sleep at night, do you ever have unpleasant, restless feelings that can be relieved by walking or movement?"

There’s really no question about it — RLS is a serious problem for many people. Those with mild symptoms might not need any medication for their symptoms. Fortunately, treatments are available for people with more severe symptoms. If the approved dopamine agonists don’t help or cause bothersome side effects, there are several other medications that might be helpful.