What is the maximum recommended dose of iron supplements (Ferrous sulfate)?

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From the FDA Drug Label

Each tablet contains 324mg of ferrous sulfate, equivalent to 65mg of elemental iron, providing 362% of the U.S. recommended daily intake (RDI) of iron for adults and children 4 and older. Each tablet contains 324 mg of ferrous sulfate, equivalent to 65 mg of elemental iron, providing 362% of the U.S. recommended daily intake (RDI) of iron for adults and children 4 and older.

The highest amount of iron in a tablet is 65mg of elemental iron per tablet, as stated in the drug labels 1 and 1.

From the Research

The highest recommended daily dose of iron tablets for adults is typically 65 mg of elemental iron, which is often found in a 325 mg ferrous sulfate tablet, as indicated by the most recent study 2. When considering the treatment of iron deficiency anemia, it's essential to weigh the benefits and risks of different iron formulations and dosages.

  • The study published in JAMA 2 highlights the importance of identifying and treating the underlying causes of iron deficiency, as well as the role of oral iron supplementation in correcting iron-deficiency anemia.
  • The use of ferrous sulfate, ferrous gluconate, and ferrous fumarate are common oral iron formulations, with varying amounts of elemental iron, as discussed in the study published in Haematologica 3.
  • However, taking more than the recommended amount can cause serious side effects, including nausea, vomiting, constipation, abdominal pain, and in severe cases, iron toxicity, as noted in the study published in Annals of hematology 4.
  • It's crucial to consult with a healthcare provider before taking high-dose iron supplements, as they will determine the appropriate dosage based on your specific condition, iron levels, and overall health status, as emphasized in the study published in Molecular aspects of medicine 5.
  • Additionally, iron supplements should be taken on an empty stomach with vitamin C to enhance absorption, but can be taken with food if stomach upset occurs, and should be kept away from children as iron overdose is a leading cause of poisoning deaths in young children, as highlighted in the study published in Terapevticheskii arkhiv 6.

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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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