Restless legs syndrome (RLS)
Restless legs syndrome (Willis-Ekbom disease) is a ** neurological-sensory disorder** causing an urge to move the legs — usually accompanied by uncomfortable sensations — worse at rest and worse in the evening/night.
It is a major cause of insomnia — often mislabelled as “anxiety” or “circulation problems” for years before diagnosis.
Diagnostic features (clinical)
All roughly true:
- Urge to move legs with unpleasant sensations
- Worse at rest — sitting, lying in bed
- Worse evening/night — circadian pattern
- Relief with movement — walking, stretching
- Often periodic limb movements during sleep — partner notices kicking
Frequency — symptoms ≥3 nights/week with significant distress warrants treatment.
Sensations described
Patients use vivid language:
- crawling, tingling, itching
- ” fizzy water in veins”
- deep ache
- electric shocks
Usually bilateral — both legs — sometimes arms in severe cases.
Primary vs secondary RLS
Primary (idiopathic)
- family history common
- starts before age 40
- gradual progression
- no clear cause — dopamine pathway dysfunction implicated
Secondary — treat cause first
| Cause | Mechanism |
|---|---|
| Iron deficiency | Low brain iron — check ferritin |
| Pregnancy | Third trimester — often resolves postpartum |
| Chronic kidney disease | Uraemia — dialysis patients high risk |
| Diabetes neuropathy | Nerve damage overlap |
| Parkinson’s | Shared dopamine pathways |
Medicines worsening RLS:
- antihistamines (sedating)
- SSRIs, SNRIs
- metoclopramide, prochlorperazine
- some antipsychotics
Review with GP — do not stop psychiatric medicines abruptly.
Investigation
GP orders:
- ferritin — treat if <75 mcg/L (some guidelines lower threshold) even if Hb normal
- FBC — iron deficiency anaemia
- U&E — kidney function
- HbA1c — diabetes
- medicine review
Neurology referral if atypical — asymmetric, progressive weakness, upper limb only onset.
Treatment ladder
Lifestyle
- sleep hygiene — see insomnia
- reduce caffeine and alcohol — especially evening
- moderate exercise — not late vigorous exercise
- leg massage, warm bath before bed
- pneumatic compression devices — some evidence
Iron supplementation
If ferritin low — oral iron (or IV if not tolerated) — recheck ferritin — RLS may resolve
Medicines (if symptoms persist)
| Drug class | Examples | Notes |
|---|---|---|
| Dopamine agonists | pramipexole, ropinirole | Very effective — augmentation risk with long use — symptoms spread, worsen |
| Alpha-2-delta ligands | gabapentin, pregabalin | NICE option — especially with pain overlap |
| Low-dose opioids | specialist only | Refractory cases |
Levodopa — occasional use — augmentation common — not first-line chronic.
Augmentation — important
Long-term dopamine agonists can worsen RLS — symptoms earlier in day, spread to arms — needs specialist switch to gabapentinoid.
RLS and pregnancy
Common third trimester — usually temporary:
- iron if deficient
- avoid medicines unless severe — specialist advice
- resolves postpartum in most
RLS vs other conditions
| Condition | Difference |
|---|---|
| Peripheral neuropathy | Constant numbness/burning — not purely movement-related relief |
| Leg cramps | Sudden painful muscle contraction — not urge to move |
| PAD | Exercise-induced claudication — vascular examination |
| Akathisia | From antipsychotics — inner restlessness whole body |
RLS is real, common, and treatable — if legs “won’t stay still” at night, ask GP for ferritin and structured treatment, not just sleeping tablets alone.
Common questions about restless legs syndrome
- What are the symptoms of restless legs syndrome?
- Uncomfortable sensations in legs — crawling, tingling, aching, itching — with irresistible urge to move them. Worse when sitting or lying, especially evening and night. Temporary relief with walking, stretching, or rubbing. Periodic limb movements during sleep often disturb partner.
- What causes restless legs syndrome?
- Primary RLS — often genetic, starts before age 40. Secondary RLS — iron deficiency, pregnancy (especially third trimester), chronic kidney disease, diabetes neuropathy, Parkinson's disease. Medicines — antihistamines, SSRIs, metoclopramide — can trigger or worsen symptoms.
- Can iron deficiency cause restless legs?
- Yes — low ferritin strongly linked even when haemoglobin is normal. Iron supplementation may resolve RLS if ferritin is low — check levels before supplementing. See iron deficiency guide if anaemic.
- How is restless legs syndrome treated?
- Treat secondary causes; improve sleep hygiene; reduce caffeine and alcohol; moderate exercise. If ferritin low — iron replacement. Medicines — pramipexole, ropinirole (dopamine agonists), gabapentin/pregabalin, low-dose opioids in refractory cases — specialist initiation. Avoid dopamine agonists without monitoring — augmentation risk long term.
- Does magnesium help restless legs?
- Evidence is weak unless genuinely deficient. Worth correcting proven deficiencies (iron more important). Unregulated high-dose supplements carry risks — test first.
- Is restless legs syndrome serious?
- Not life-threatening but significantly affects sleep and quality of life — linked to insomnia, depression, and cardiovascular risk through sleep deprivation. Treating RLS improves sleep and daytime function.