What is the treatment for a ferritin level of 5, indicating severe iron deficiency?

Treatment for Severe Iron Deficiency with Ferritin of 5

Oral iron supplementation with ferrous sulfate 324 mg (65 mg elemental iron) daily is the first-line treatment for severe iron deficiency with a ferritin of 5 μg/L, with intravenous iron reserved for specific circumstances such as malabsorption, intolerance, or ongoing blood loss.

Diagnosis Confirmation

A ferritin level of 5 μg/L indicates severe iron deficiency, well below all established thresholds:

• Below 30 μg/L in non-inflammatory states 1
• Below 45-50 μg/L as recommended by the American Gastroenterological Association 2
• Below 100 μg/L in inflammatory conditions 3

This extremely low value requires prompt treatment to prevent or address iron deficiency anemia and associated symptoms.

Treatment Algorithm

First-Line Treatment: Oral Iron Therapy

1. Oral Iron Formulation:

   • Ferrous sulfate 324 mg (containing 65 mg elemental iron) daily 4
   • Alternative dosing: Consider alternate-day dosing to improve absorption and reduce side effects 5

2. Administration Tips:

   • Take on an empty stomach for optimal absorption
   • If GI side effects occur, may take with food (though absorption will be reduced)
   • Take with 500 mg vitamin C to enhance absorption 2
   • Avoid taking with calcium, fiber, tea, coffee, or antacids which inhibit absorption

3. Duration of Treatment:

   • Continue for 3-6 months after normalization of hemoglobin to replenish iron stores
   • Target ferritin >50 μg/L 6, 7

Second-Line Treatment: Intravenous Iron

Consider IV iron in the following circumstances:

• Failure to respond to oral iron after 4-8 weeks
• Intolerance to oral iron (significant GI side effects)
• Malabsorption disorders (celiac disease, inflammatory bowel disease)
• Ongoing blood loss exceeding oral iron absorption capacity
• Need for rapid repletion (symptomatic anemia) 2

Monitoring Response

1. Initial Follow-up:

   • Repeat complete blood count and iron studies (ferritin, transferrin saturation) after 8-10 weeks of treatment 1

2. Long-term Monitoring:

   • After normalization, monitor every 6-12 months in patients at risk for recurrence 1

Addressing Underlying Causes

Simultaneously investigate and address potential causes of iron deficiency:

• Gastrointestinal blood loss (requires endoscopic evaluation)
• Heavy menstrual bleeding in women
• Malabsorption disorders (celiac disease, H. pylori infection)
• Dietary insufficiency
• Pregnancy

Special Considerations

1. Inflammatory Conditions:

   • In patients with inflammatory bowel disease, chronic kidney disease, or heart failure, IV iron may be preferred over oral iron 2, 8
   • Higher ferritin thresholds apply for diagnosing iron deficiency (up to 100 μg/L) 3

2. Cautions:

   • Avoid long-term iron supplementation once ferritin normalizes, as excess iron can be harmful 1
   • Withhold iron during active infections 8

Common Pitfalls to Avoid

1. Inadequate duration of therapy - Treatment should continue well beyond normalization of hemoglobin to replenish iron stores
2. Failure to investigate underlying cause - Iron deficiency is a symptom, not a diagnosis
3. Overreliance on hemoglobin alone - Monitor both hemoglobin and ferritin to ensure complete iron repletion
4. Ignoring side effects - Poor adherence due to GI side effects is common; address proactively

By following this approach, most patients with severe iron deficiency will achieve normalization of iron stores and resolution of associated symptoms, improving quality of life and preventing complications of chronic iron deficiency.