Iron deficiency anaemia is a common problem. The majority of patients are treated with oral iron supplements.
The current recommended dosage for oral supplementation of 200 mg ferrous fumarate 3x per day however, is based on a single small study of poor quality.
There is no consensus concerning parenteral dosing.
In recent years, new insights have been gained regarding both the dosage of oral supplementation and the indication for parenteral supplementation.
Oral therapy is preferred. In principle, 100 mg ferrous fumarate once a day is sufficient for the treatment of symptom-free patients with anaemia.
In cases of severe anaemia, or in patients with symptoms, 200 mg/day should be prescribed. If side effects appear, it can be dosed every other day.
Where oral therapy does not show effectiveness, the anaemia is severe, or rapid increase of haemoglobin is indicated, parenteral supplementation should be chosen.
Parenteral supplementation is more effective than oral supplementation in specific conditions, such as dialysis-dependent renal insufficiency, heart failure or active IBD.
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