From the Guidelines
The starting dose of iron supplementation for an anemic patient should be 50-100 mg of elemental iron per day, taken orally in the fasting state, with ferrous sulfate 200 mg tablet being a suitable option. This recommendation is based on the British Society of Gastroenterology guidelines for the management of iron deficiency anaemia in adults 1. The guidelines suggest that a once daily dose of 50-100 mg of elemental iron may be the best compromise option for initial treatment.
When choosing an iron supplement, it is essential to consider the elemental iron content, as this varies among different formulations. For example, ferrous sulfate 200 mg tablets contain 65 mg of elemental iron, while ferrous fumarate 210 mg tablets contain 69 mg of elemental iron 1.
It is also crucial to monitor the initial haematological response to iron therapy and modify the treatment regimen as needed. The absence of an Hb rise of at least 10 g/L after 2 weeks of daily oral iron therapy is strongly predictive of subsequent failure to achieve a sustained haematological response 1.
In addition to monitoring haemoglobin levels, it is essential to investigate the underlying cause of anaemia and address any underlying conditions that may be contributing to the anaemia. The patient should be counseled that iron supplementation typically takes 2-3 weeks to significantly improve haemoglobin levels, and treatment should continue for at least 3 months to replenish iron stores.
Regular haemoglobin monitoring is recommended to ensure an ultimately satisfactory response, with a suggested interval of every 4 weeks until the haemoglobin is in the normal range 1.
If the patient experiences gastrointestinal side effects, such as nausea or abdominal pain, consideration can be given to alternative formulations, such as ferrous gluconate or ferric maltol, which may be better tolerated 1. However, the standard practice of switching to a different traditional iron salt is not supported by evidence, and parenteral iron may be a more effective option in certain cases, such as chronic disease or impaired absorption 1.
From the FDA Drug Label
DIRECTIONS FOR USE: Do not crush or chew tablets. Adult Serving Size: 1 tablet two to three times daily. The starting dose of iron supplementation for an anemic patient is 1 tablet two to three times daily of ferrous sulfate (PO) 2.
From the Research
Iron Supplementation Dosage
The starting dose of iron supplementation for an anemic patient can vary depending on the specific circumstances and the type of iron supplement used.
- The study 3 found that 3 mg/kg of elemental iron once daily as either ferrous sulfate drops or iron polysaccharide complex drops for 12 weeks was effective in increasing hemoglobin concentration in infants and children with nutritional iron-deficiency anemia.
- Another study 4 used a daily supplement of 30 mg/day of elemental iron as ferrous sulfate or iron bis-glycinate chelate for 12 weeks in schoolchildren with iron deficiency but without anemia, and found that it increased ferritin concentration.
- The study 5 used ferric citrate (2 g three times a day with meals) or ferrous sulfate (325 mg three times a day) for 12 weeks in patients with moderate to severe CKD and iron deficiency, and found that ferric citrate resulted in a greater increase in TSAT and ferritin concentrations.
Types of Iron Supplements
Different types of iron supplements are available, including:
- Ferrous sulfate: a commonly prescribed oral iron supplement 6, 3, 4, 5
- Iron polysaccharide complex: possibly better tolerated than ferrous sulfate 3
- Ferric maltol: a novel iron formulation 6
- Nanoparticle encapsulated sucrosomial iron: a novel iron formulation 6
- Iron bis-glycinate chelate: may be better tolerated than ferrous sulfate 4
- Ferric citrate: an oral medication approved for treatment of iron deficiency anemia in patients with CKD not requiring dialysis 5