Definition and epidemiology
Restless legs syndrome (RLS, Willis–Ekbom disease) is a sensorimotor sleep disorder defined by an urge to move the legs, typically with uncomfortable sensations, that worsens at rest and in the evening and is relieved by movement. Prevalence in children and adolescents is estimated at ~2%, with roughly a quarter reporting moderate-to-severe symptoms. There is a strong family history in early-onset cases and frequent overlap with periodic limb movements of sleep (PLMS), ADHD, and iron deficiency. RLS is widely under-recognised in children because they describe symptoms in their own words (“creepy-crawlies”, “want to kick”, “boo-boos”, “energy in my legs”) and because daytime consequences (inattention, irritability, fatigue) often dominate the picture.
Clinical features
- An urge to move the legs, usually with unpleasant sensations
- Symptoms begin or worsen at rest (lying/sitting) and in the evening/night
- Partial or complete relief with movement (walking, stretching, kicking)
- Sleep-onset insomnia, restless sleep, frequent night waking
- Daytime sequelae: inattention, hyperactivity, mood lability, poor school performance
- Often a parent or sibling with RLS
Diagnosis
Diagnosis is clinical. The 2013 IRLSSG pediatric criteria require all five essential features (now aligned with the adult criteria), applied with developmentally appropriate language:
- Urge to move the legs, usually accompanied by/caused by uncomfortable sensations
- Worse during rest or inactivity
- Partially or totally relieved by movement
- Worse in the evening/night than during the day
- Not solely accounted for by a mimic (positional discomfort, leg cramps, myalgia, arthralgia, habitual foot tapping, growing pains)
The child must describe the symptoms in their own words; observation and parental corroboration support the diagnosis in younger children. Polysomnography is not required to diagnose RLS but documents a PLMS index ≥5/h when supportive evidence is needed. A core workup is serum ferritin and iron studies — iron deficiency (commonly ferritin below ~50 µg/L) is the most important modifiable contributor.
See the full criteria: Restless Legs Syndrome
Red flags / when to reconsider
- Unilateral, fixed, or daytime-only leg symptoms — consider orthopaedic/neurologic causes
- Sensory loss, weakness, or abnormal reflexes — evaluate for neuropathy/radiculopathy
- Nocturnal pain without the urge-to-move/relief-by-movement pattern — likely growing pains or cramps, not RLS
- Failure to respond to iron repletion with a genuinely low ferritin — re-examine the diagnosis
Management overview
Management is non-pharmacologic first. Correct iron deficiency — oral iron when ferritin is low is the single most evidence-based intervention and can resolve symptoms; recheck ferritin after a course. Optimise sleep hygiene, ensure adequate sleep duration, and reduce evening caffeine; review medications that can aggravate RLS (some antihistamines, dopamine-blocking antiemetics, and certain antidepressants). Treat comorbid ADHD and screen for obstructive sleep apnoea. Pharmacologic therapy (alpha-2-delta ligands or dopaminergic agents) is reserved for refractory, impairing symptoms and is initiated and monitored by a sleep/neurology specialist given limited pediatric licensing and the risk of augmentation with dopaminergics. This monograph gives no specific doses.
References
- Picchietti DL, et al. Pediatric RLS diagnostic criteria: IRLSSG update. Sleep Med. 2013;14:1253–1259.
- Allen RP, et al. Updated IRLSSG consensus diagnostic criteria. Sleep Med. 2014;15:860–873.
- DelRosso LM, Bruni O. Treatment of pediatric RLS and PLMD. Sleep Med Clin. 2021;16:305–314.
Decision support for qualified clinicians only — verify against current primary guidelines and your clinical judgement.