What Is Restless Leg Syndrome?

Medical Author: Melissa Stoppler, M.D.
Medical Editor: Barbara K. Hecht, Ph.D.

Restless leg syndrome (RLS), also known as nocturnal myoclonus, is a type of sleep disorder characterized by uncomfortable sensations in the legs and an uncontrollable desire to move the legs. These abnormal sensations usually occur in the lower legs shortly after going to bed. During the early stages of sleep, these episodes of leg movement often last up to an hour.

The abnormal sensations of RLS are quite variable. They have been described as a crawling, creeping, pulling, drawing, tingling, pins and needles, or prickly discomfort. They are not cramping in character.

Sometimes these sensations occur in the feet, thighs or even arms. Although RLS is considered to be a sleep disorder, some people also experience these sensations during the day, particularly when lying down.