Quick answer. Restless legs syndrome (RLS) is a common neurological sleep disorder causing an uncomfortable, irresistible urge to move the legs. The urge is typically worse at rest and in the evening or night, and is temporarily relieved by movement such as walking or stretching, which is why it disrupts sleep. Many cases are idiopathic, but iron deficiency is an important and treatable cause; pregnancy and kidney disease also raise risk. In Singapore, RLS is diagnosed clinically and a blood test (including ferritin) is often done. Treatment may include iron supplements if levels are low, lifestyle changes, and medication for moderate-to-severe cases. See a doctor if symptoms disturb your sleep.
Restless legs syndrome (RLS), also called Willis-Ekbom disease, is a neurological sleep disorder marked by an uncomfortable urge to move the legs, usually accompanied by sensations described as crawling, tingling, aching or “electric”. The hallmark is that symptoms appear or worsen at rest and in the evening or night, and are eased by movement. Because the urge intensifies when you lie down to sleep, RLS is a frequent cause of insomnia and daytime tiredness.
RLS is often overlooked or dismissed as “just nerves” in Singapore, yet it is treatable. Importantly, a low iron store (even without anaemia) is one of the most common and correctable triggers. This guide explains the causes, how RLS is diagnosed and treated here, and when to see a doctor.
At a glance
| Feature | Typical of RLS | Why it matters |
|---|---|---|
| Urge to move legs | Strong, often with unpleasant crawling or aching sensations | Core symptom; usually affects both legs |
| Timing | Worse at rest and in the evening or night | Distinguishes RLS from leg cramps or restlessness from anxiety |
| Relief | Eased by walking, stretching or moving the legs | A defining clinical clue |
| Sleep impact | Difficulty falling or staying asleep; daytime sleepiness | Drives most people to seek help |
| Common treatable cause | Low iron stores (low ferritin), with or without anaemia | Iron replacement can markedly improve symptoms |
What restless legs syndrome feels like
People with RLS describe a deep, hard-to-ignore urge to move the legs, often paired with uncomfortable sensations such as crawling, tingling, pulling, throbbing or aching. The discomfort is felt inside the legs rather than on the skin. Four features typically define it:
- Urge to move the legs, usually with unpleasant sensations.
- Worse at rest – when sitting or lying down.
- Relief with movement – walking or stretching helps, at least temporarily.
- Evening or night-time pattern – symptoms peak when you are trying to sleep.
Many people also experience repetitive leg jerks during sleep (periodic limb movements), which can further fragment sleep and tire a bed partner.
Causes: why iron deficiency matters
RLS is often idiopathic (no single cause found) and can run in families. However, several secondary causes are important because they are treatable:
- Iron deficiency – low body iron stores (low ferritin) are strongly linked to RLS, even when you are not anaemic. Iron is needed to make dopamine in the brain, which helps control movement.
- Pregnancy – RLS is common in pregnancy, especially the third trimester, and usually settles after delivery.
- Chronic kidney disease – RLS is frequent in people on dialysis.
- Other factors – certain medicines (some antidepressants, antihistamines, anti-nausea drugs), caffeine, alcohol and nicotine can worsen symptoms.
Because iron deficiency is both common and correctable, checking and treating it is a key first step.
How RLS is diagnosed in Singapore
RLS is a clinical diagnosis – there is no single test that confirms it. A doctor will ask about the four core features above, the timing and triggers, your sleep, family history, medications, and conditions such as pregnancy or kidney disease.
A blood test is usually arranged to check iron status, including ferritin (a marker of iron stores), full blood count and kidney function. A sleep study (polysomnography) is not needed to diagnose RLS itself, but may be ordered if another sleep disorder such as obstructive sleep apnoea is suspected, or to document periodic limb movements. In Singapore, RLS is managed by neurologists and sleep physicians, including at restructured hospital sleep services.
Treatment options
Treatment is tailored to severity:
- Treat low iron first. If ferritin is low, your doctor may prescribe iron supplements, which can substantially improve or resolve symptoms. Iron should only be taken under medical guidance, as excess iron is harmful; intravenous iron is reserved for selected cases.
- Lifestyle measures. Regular moderate exercise, good sleep habits, leg stretching or massage, warm baths, and cutting back on caffeine, alcohol and nicotine can help. Reviewing medicines that may aggravate RLS is also useful.
- Medication. For moderate-to-severe or persistent RLS, doctors may prescribe specific medicines. These can be effective but need monitoring (for example, to avoid a phenomenon called augmentation, where symptoms worsen over time on some drugs). Do not self-medicate.
RLS is usually manageable rather than “cured”, but most people gain good control with the right combination of approaches.
RLS in pregnancy
RLS commonly appears or worsens during pregnancy, particularly the third trimester, and typically improves after the baby is born. Iron and folate status are often checked, since deficiency can contribute. Because many RLS medicines are not suitable in pregnancy, management usually focuses on iron correction (if needed) and lifestyle measures. Always discuss any supplements or treatments with your obstetrician or doctor before starting them.
When to see a doctor
See a doctor if leg discomfort and the urge to move:
- Regularly disrupts your sleep or affects your daytime energy, mood or concentration.
- Is getting more frequent or severe.
- Occurs alongside symptoms of anaemia (tiredness, pallor, breathlessness) or kidney disease.
- Appears during pregnancy and is distressing.
A simple blood test for iron stores can reveal a treatable cause. You can start with a GP, who can arrange tests and refer you to a neurologist or sleep specialist if needed.
Related guides
- Best Respiratory & Lung Clinics in Singapore — our editorial shortlist
- Narcolepsy
- Sleep study (polysomnography)
- Shift work & jet lag
Sources
- SingHealth – Sleep Disorders: Conditions & Treatments
- SGH – Sleep Centre (Singapore General Hospital)
- NTFGH – Sleep Disorders Multi-disciplinary Care (includes restless legs syndrome)
- NIH/PMC – Iron for the treatment of restless legs syndrome (review)
Related conditions & guides
Related conditions and guides you may find useful:
- Insomnia Treatment in Singapore
- Obstructive Sleep Apnoea and CPAP in Singapore
- Snoring & Obstructive Sleep Apnoea (OSA) Treatment in Singapore
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