Restless Legs Syndrome Management
Diagnosis and Pathophysiology
- Restless Legs Syndrome (RLS) results from central dopaminergic dysfunction combined with brain iron deficiency, with genetic predisposition playing a major role in primary cases 1, 2
- Impaired dopamine transport in the substantia nigra due to reduced intracellular iron plays a critical role 1, 2
- The spinal cord, peripheral nerves, and central dopamine and narcotic receptors are involved in pathophysiology 1, 2
- Iron deficiency is the most important treatable secondary cause of RLS, with a threshold of ferritin <50 ng/mL 1, 2
Clinical Symptoms and Diagnostic Criteria
- RLS is diagnosed clinically using four essential criteria, with symptoms characteristically worsening at night and relieved by movement 1, 2
- The four essential diagnostic criteria include: urge to move the legs, symptoms beginning or worsening during rest or inactivity, symptoms partially or totally relieved by movement, and symptoms worsening or only occurring in the evening or night 1, 2
Management Algorithm
- Check morning fasting serum ferritin and transferrin saturation in all patients before starting any medication, avoiding iron-containing supplements for 24 hours prior 3, 4, 5
- Iron supplementation is indicated if ferritin ≤75 ng/mL or transferrin saturation <20% 3, 4, 5
- Alpha-2-delta ligands (gabapentin, gabapentin enacarbil, or pregabalin) are strongly recommended as first-line therapy over dopamine agonists 3, 4, 5
- Gabapentin should be started at 300 mg three times daily and titrated by 300 mg/day every 3-7 days until reaching a maintenance dose of 1800-2400 mg/day divided three times daily 4, 5
Special Considerations
- In pregnancy, consider pregnancy-specific safety profile of each treatment and iron supplementation is particularly important, with oral formulations favored throughout gestation 3, 4
- In pediatric RLS, oral ferrous sulfate is conditionally recommended if ferritin <50 ng/mL, and monitor for constipation with iron supplementation 3, 4