What is the recommended treatment and dosage for iron deficiency anemia using ferrous (iron) fumarate?

Treatment of Iron Deficiency Anemia with Ferrous Fumarate

The recommended treatment for iron deficiency anemia is ferrous fumarate 200 mg once daily, which should be continued for 3 months after normalization of hemoglobin levels to ensure adequate replenishment of iron stores. 1

Dosing Recommendations

• Standard dosing for adults is ferrous fumarate 200 mg once daily (providing approximately 65-106 mg of elemental iron) 1
• For patients with severe anemia or symptoms, dosing may be increased to 200 mg twice daily 2
• If gastrointestinal side effects occur, consider:
  • Reducing to every other day dosing [2, @18@]
  • Switching to alternative iron preparations (ferrous sulfate or ferrous gluconate) 1
  • Using liquid formulations for patients who cannot tolerate tablets 1

Duration of Treatment

• Continue oral iron therapy for 3 months after hemoglobin normalization to fully replenish iron stores 1
• Monitor hemoglobin response within the first 4 weeks of treatment 1
• Expect hemoglobin to rise by approximately 2 g/dL after 3-4 weeks of proper treatment 1

Monitoring and Follow-up

• Check hemoglobin levels after 4 weeks to confirm response to therapy 1
• Once normalized, monitor hemoglobin and red cell indices at 3-month intervals for the first year, then after another year 1
• Additional iron supplementation should be given if hemoglobin or red cell indices fall below normal 1

Special Considerations

• Adding ascorbic acid (vitamin C) 250-500 mg twice daily may enhance iron absorption when response is poor 1
• Avoid consuming tea and coffee within one hour of taking iron supplements as they inhibit absorption 1
• For patients with inflammatory bowel disease, no more than 100 mg elemental iron per day is recommended 1

When to Consider Parenteral Iron

Intravenous iron should be considered when:

• Oral iron is not tolerated despite trying at least two different preparations 1
• There is inadequate response to oral therapy 1
• Rapid correction of anemia is needed 2
• Patient has conditions affecting absorption (inflammatory bowel disease, post-bariatric surgery) 1, 2

Common Pitfalls

• Failure to continue treatment for the full 3 months after hemoglobin normalization, leading to incomplete replenishment of iron stores 1
• Inadequate response to therapy may be due to:
  • Poor compliance 1
  • Misdiagnosis of the type of anemia 1
  • Continued blood loss 1
  • Malabsorption issues 1
• Transfusion should be limited to symptomatic severe anemia, and iron replacement therapy is still necessary post-transfusion [1, @19@]

By following these guidelines for ferrous fumarate administration, most patients with iron deficiency anemia will achieve normalization of hemoglobin levels and replenishment of iron stores, improving their quality of life and reducing morbidity associated with anemia.