Restless legs syndrome (RLS) is a disorder of the part of the nervous system that affects the legs and causes an urge to move them. Because it usually interferes with sleep, it also is considered a sleep disorder.

Patients with periodic limb movement disorder (PLMD) or restless legs syndrome (RLS) experience a jerking of the legs during sleep which cause frequent brief arousals and a poor quality of sleep. Before bedtime, individuals with RLS may have unusual sensations in the legs and arms that prompt movement to bring relief. These conditions may affect up to 30% of the population over age 65. There are a number of medication options which may be helpful in controlling symptoms and improving daytime functioning.