Restless Legs Syndrome (RLS)

A neurological sensorimotor disorder characterized by uncomfortable urges to move the legs, especially at rest and during the evening/night.

Pathophysiology:

• Dopamine dysregulation in the CNS
• Often associated with iron deficiency (↓ brain iron levels affect dopamine pathways)

1. Urge to move the legs, usually with uncomfortable sensations
2. Worse at rest (sitting or lying)
3. Relieved by movement
4. Worse in the evening/night
5. Not better explained by another condition

Common Causes / Associations:

• Primary (idiopathic) - usually familial and chronic
• Secondary causes (important for Step 2):
  • Iron deficiency anemia
  • Chronic kidney disease
  • Pregnancy (especially 3rd trimester)
  • Diabetes, multiple sclerosis, Parkinson’s
  • Certain medications: antidepressants, antipsychotics, antihistamines

Workup:

• Check serum ferritin (low iron = treatable cause)

Treatment:

1. Non-Pharmacologic:

• Avoid caffeine, alcohol, nicotine
• Maintain good sleep hygiene
• Moderate exercise, stretching

2. Treat Underlying Cause:

• Iron supplementation if ferritin <75 ng/mL (even if not anemic)

3. Pharmacologic (for moderate–severe RLS):

• Dopamine agonists: Pramipexole, Ropinirole (first-line)
• Alpha-2-delta ligands: Gabapentin, Pregabalin (especially if comorbid pain or insomnia)
• Consider opioids only in refractory, severe cases

• If patient has RLS symptoms + iron deficiency, treat with oral iron first, even if hemoglobin is normal.
• Pregnancy-related RLS is treated supportively; iron is administered if deficient.