From the Guidelines
Ferrous sulfate is the preferred choice for iron supplementation due to its lower cost and higher elemental iron content, despite no single formulation having advantages over others in terms of efficacy. The most recent and highest quality study, published in 2024 in the Clinical Gastroenterology and Hepatology journal, states that no single formulation of oral iron has any advantages over any other, but ferrous sulfate is preferred as the least expensive iron formulation 1. Some key points to consider when choosing between ferrous sulfate and ferrous gluconate include:
- Elemental iron content: Ferrous sulfate typically contains more elemental iron per dose compared to ferrous gluconate.
- Cost: Ferrous sulfate is often less expensive than ferrous gluconate.
- Availability: Ferrous sulfate is more widely available than ferrous gluconate.
- Tolerability: Both forms can cause gastrointestinal side effects, but ferrous gluconate may be better tolerated in some individuals.
- Treatment duration: Treatment usually continues for 3-6 months to replenish iron stores. It's also worth noting that taking iron supplements with vitamin C can enhance absorption, and individual factors like tolerance, cost, and availability may influence the choice between ferrous sulfate and ferrous gluconate. However, according to the British Society of Gastroenterology guidelines, the initial treatment of iron deficiency anemia should be with one tablet per day of ferrous sulphate, fumarate or gluconate, with adjustments made if not tolerated 1.
From the Research
Comparison of Ferrous Sulfate and Ferrous Gluconate
There are no direct studies comparing ferrous sulfate and ferrous gluconate in the provided evidence. However, the following information can be gathered from the available studies:
- Ferrous sulfate is compared to other iron formulations, such as ferric iron polymaltose complex and iron polysaccharide complex, in several studies 2, 3, 4, 5.
- The studies suggest that ferrous sulfate is an effective treatment for iron deficiency anemia, with good bioavailability and acceptable tolerability 2, 3, 4, 5.
- One study compares ferrous sulfate to ferrous glycinate chelate, which is a different iron formulation, and finds that ferrous sulfate has better results in hematologic laboratory parameters 6.
- Another study compares ferrous sulfate to iron polysaccharide complex and finds that ferrous sulfate results in a greater increase in hemoglobin concentration at 12 weeks 4.
Key Findings
- Ferrous sulfate is an effective treatment for iron deficiency anemia, with good bioavailability and acceptable tolerability 2, 3, 4, 5.
- Ferrous sulfate may have better results in hematologic laboratory parameters compared to other iron formulations, such as ferric iron polymaltose complex and iron polysaccharide complex 2, 3, 4, 5.
- Ferrous sulfate may have better results in hematologic laboratory parameters compared to ferrous glycinate chelate 6.
Study Results
- A study of 399 patients with iron deficiency anemia found that ferrous sulfate was as effective as Ferrograd® in increasing hemoglobin levels, with a lower incidence of gastrointestinal adverse events 3.
- A study of 80 infants and children with nutritional iron-deficiency anemia found that ferrous sulfate resulted in a greater increase in hemoglobin concentration at 12 weeks compared to iron polysaccharide complex 4.
- A study of 118 children with iron deficiency anemia found that ferrous sulfate had a better clinical response and fewer adverse effects compared to iron polymaltose complex 5.
- A study of 18 gastrectomized patients with iron deficiency anemia found that ferrous sulfate had better results in hematologic laboratory parameters compared to ferrous glycinate chelate 6.