What is the recommended ferrous fumarate (Iron(II) fumarate) regimen as per the British National Formulary (BNF)?

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From the Research

The recommended ferrous fumarate regimen for iron deficiency anemia is 100 mg once daily for symptom-free patients, and 200 mg/day for patients with severe anemia or symptoms, as supported by the most recent study 1. The dosage of ferrous fumarate can be adjusted based on the severity of the anemia and the presence of symptoms.

  • For symptom-free patients with anaemia, 100 mg ferrous fumarate once a day is sufficient 1.
  • In cases of severe anaemia, or in patients with symptoms, 200 mg/day should be prescribed 1.
  • If side effects appear, it can be dosed every other day 1. The treatment should continue for about 3-6 months to replenish iron stores, though hemoglobin levels usually normalize within 2-4 weeks. Ferrous fumarate should be taken on an empty stomach if possible, as food can reduce absorption by up to 40%, but it can be taken with food if gastrointestinal side effects occur. Common side effects include nausea, epigastric pain, constipation, and diarrhea, which can be minimized by starting with a lower dose and gradually increasing, or by temporarily reducing the dose. Liquid formulations are available for those who have difficulty swallowing tablets. Ferrous fumarate works by providing the iron needed for hemoglobin production, which carries oxygen in red blood cells, thus treating the underlying cause of iron deficiency anemia. It's worth noting that the most recent study 2 compared the efficacy of thrice-weekly versus thrice-daily oral ferrous fumarate treatment in adult patients with iron-deficiency anemia, and found that the thrice-weekly regimen was non-inferior to the thrice-daily regimen, with fewer gastrointestinal side effects. However, the study 1 provides the most straightforward and recent guidance on the dosage of ferrous fumarate.

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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