Restless legs syndrome (RLS) is a neurologic condition marked by a strong, often difficult-to-resist urge to move the legs. The urge is usually accompanied by unpleasant or hard-to-describe sensations and is most noticeable in the evening, at night, or during periods of rest. Movement often brings temporary relief. ^[1][3]

RLS is more than simple “leg restlessness.” It can interfere with falling asleep, staying asleep, and daytime functioning. Symptoms may become especially noticeable while sitting through a meeting, taking a long car ride, watching a movie, or lying in bed. For many people, the disorder affects quality of life through chronic sleep disruption, fatigue, irritability, and reduced concentration. ^[1][2]

What are the symptoms?

The hallmark symptom is an urge to move the legs that begins or worsens during rest and improves with movement. Mayo Clinic notes that symptoms often start when a person is sitting or lying down, become worse in the evening, and ease temporarily with walking or stretching. Patients may describe the sensation as pulling, tingling, crawling, burning, tension, or an inner sense of unease. ^[1]

Symptoms usually affect both legs, although severity may be unequal. In some people, the arms can also be involved. Repetitive leg movements in bed, difficulty falling asleep, and periodic limb movements noticed by a bed partner may accompany the condition. Over time, poor sleep can contribute to daytime tiredness, impaired work performance, mood changes, and decreased quality of life. ^[1][3]

What causes it?

The cause is not always clear. Some cases are primary, meaning no obvious underlying cause is identified. In others, RLS may be associated with iron deficiency, pregnancy, kidney disease, peripheral neuropathy, or other medical conditions. For that reason, once RLS is suspected, clinicians do not only evaluate the symptoms themselves but also look for conditions that may be contributing to them. ^[2][3]

Iron deficiency is particularly important. Mayo Clinic emphasizes that symptoms may improve in some patients when an underlying cause such as low iron is corrected. One reason may be the relationship between iron and dopamine function within the central nervous system. This is why blood testing is often part of the workup. Rather than taking iron supplements at random, it is safer to proceed on the basis of measured deficiency and medical supervision. ^[2]

Who gets it more often and what can worsen it?

RLS can begin at any age, but it often becomes more noticeable with advancing age. Earlier onset may be seen in people with a family history. Prolonged inactivity, irregular sleep habits, certain medications, alcohol, caffeine, and nicotine can make symptoms worse. Daily habits therefore matter not only as triggers but also as part of management. ^[1][3]

RLS symptoms may also occur during pregnancy and often improve after delivery. Still, not every uncomfortable leg sensation in pregnancy is RLS. Varicose veins, muscle cramps, fluid-electrolyte imbalance, and other sleep-related problems can cause similar complaints. New, severe, or sleep-disrupting symptoms deserve individualized evaluation. ^[1][3]

How is it diagnosed?

Diagnosis is usually clinical and based on the patient’s history. Leg discomfort that begins during rest, improves with movement, and becomes worse in the evening is central to the diagnosis. Physical examination and neurologic assessment help rule out other conditions that can produce similar symptoms. A sleep test is not required for most patients, although it may be considered if another sleep disorder is suspected. ^[2]

Blood tests are important, especially to look for correctable causes such as iron deficiency. Kidney function, medication use, and signs of neuropathy may also be reviewed when relevant. Accurate diagnosis depends not only on matching a symptom pattern but also on reasonably excluding other causes of similar complaints. ^[2][3]

How is it treated?

The first step is to identify and treat any underlying cause. If iron deficiency is present, iron replacement may be recommended, sometimes by mouth and in some cases intravenously. Iron should not be started without guidance, because unnecessary supplementation can cause side effects and create false reassurance. ^[2]

When no correctable cause is found, or when symptoms persist despite correction, lifestyle measures become important. Keeping a regular sleep schedule, avoiding caffeine late in the day, engaging in moderate exercise, minimizing prolonged inactivity, and reviewing symptom-worsening medications with a physician may help. If symptoms remain troublesome, prescription medications can be considered, but drug choice should be individualized according to age, symptom burden, and coexisting conditions. ^[1][2][3]

When should you see a doctor?

Medical evaluation is appropriate if symptoms continue for weeks, disturb sleep, cause daytime fatigue or concentration problems, or occur alongside pregnancy, kidney disease, diabetes, or neuropathy. By contrast, one-sided swelling, sudden pain, redness, or muscle weakness affecting walking may suggest a different vascular or neurologic problem rather than RLS. ^[1][2]

Restless legs syndrome is frustrating but treatable. Taking symptoms seriously and evaluating potentially reversible contributors—especially iron deficiency and sleep disruption—can improve outcomes. A neurology or sleep medicine assessment is safer than self-diagnosis. ^[1][2][3]

FAQ

Why does restless legs syndrome get worse at night?

Because RLS symptoms typically become more noticeable in the evening and at night, especially during rest. This day-night pattern is one of the characteristic features of the disorder. ^[1][3]

Can iron deficiency cause RLS?

Yes. In some people, iron deficiency can trigger or worsen RLS symptoms. That is why blood tests are often part of the evaluation. ^[2]

Is a sleep study required?

No. RLS is usually diagnosed clinically. A sleep study may be useful only if another sleep disorder is also suspected. ^[2]

Can exercise help?

Moderate, regular exercise and avoiding long periods of inactivity may help many people. Very intense exercise, however, can worsen symptoms in some cases. ^[1][3]

Which symptoms may suggest another condition?

One-sided swelling, redness, sudden pain, or muscle weakness are less typical for RLS and may point to a vascular or neurologic problem that should be assessed separately. ^[1][2]