From the Guidelines
To increase ferritin levels in a patient with Restless Legs Syndrome (RLS) and low ferritin, I recommend starting oral iron supplementation with ferrous sulfate 325 mg taken once or twice daily between meals with vitamin C (such as orange juice or a 500 mg vitamin C supplement) to enhance absorption. This approach is supported by the American Academy of Sleep Medicine's clinical practice guideline, which suggests the use of ferrous sulfate over no ferrous sulfate in patients with appropriate iron status 1. The guideline emphasizes the importance of iron supplementation in managing RLS symptoms, particularly in patients with low ferritin levels.
When implementing this regimen, it is essential to consider the following:
- Take the iron supplement on an empty stomach, at least 1 hour before or 2 hours after meals
- Separate the iron supplement from calcium supplements, dairy products, coffee, tea, and antacids by at least 2 hours to minimize interference with iron absorption
- Start with a lower dose and gradually increase as needed to manage common side effects such as constipation, nausea, and dark stools
- Consider switching to a gentler formulation like ferrous gluconate if side effects persist
The target ferritin level for RLS management is typically above 75 ng/mL, with some experts recommending levels above 100 ng/mL for optimal symptom control 1. Regular monitoring of ferritin levels is crucial to ensure appropriate dosing and adjust the treatment plan as needed. If oral supplementation is not effective or not tolerated, intravenous iron therapy might be considered under medical supervision. It is also important to note that iron therapy should be carefully managed, with iron stored safely in a locked cabinet in the home to prevent acute overdose, which can be fatal 1.
From the Research
Increasing Ferritin Levels in Patients with Restless Legs Syndrome (RLS) and Low Ferritin
To increase ferritin levels in patients with RLS and low ferritin, the following methods can be considered:
- Iron supplementation: Studies have shown that iron supplements can relieve RLS symptoms and lower the risk of RLS augmentation in patients with iron deficiency 2, 3, 4, 5, 6.
- Oral iron: Oral iron supplementation (65 mg elemental iron) is possibly effective for treating RLS in patients with serum ferritin ≤75 μg/l 4.
- Intravenous iron: Ferric carboxymaltose (1000 mg) is effective for treating moderate to severe RLS in patients with serum ferritin <300 μg/l and can be used as first-line treatment for RLS in adults 4.
- Monitoring ferritin levels: Regular monitoring of ferritin levels is essential to determine the effectiveness of iron supplementation and to adjust treatment accordingly 2, 3, 4, 5, 6.
Treatment Considerations
When treating patients with RLS and low ferritin, the following considerations should be taken into account:
- Non-dopaminergic agents: Non-dopaminergic agents should be considered as the first-line treatment for patients with persistent low serum ferritin levels or those with moderate to severe RLS to prevent augmentation 2.
- Iron treatment algorithms: New iron treatment algorithms, based on evidence and consensus opinion, have been developed to guide treatment decisions 4.
- Patient characteristics: Patient characteristics, such as family history of RLS, secondary sleep disorders, medical diagnoses, and/or mental health diagnoses, may affect treatment outcomes 3.