What is the appropriate dosing for ferrous sulfate (Iron Supplement)?

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From the Guidelines

Ferrous sulfate should be dosed at one tablet per day for the initial treatment of iron deficiency anemia in adults, as recommended by the British Society of Gastroenterology guidelines [1@]. The guidelines suggest that if the patient does not tolerate the initial dose, a reduced dose of one tablet every other day, alternative oral preparations, or parenteral iron should be considered [1@].

Key Considerations

  • The dose of ferrous sulfate can be adjusted based on patient tolerance and response to treatment.
  • Other oral iron preparations, such as ferrous fumarate or gluconate, may be considered if the patient does not tolerate ferrous sulfate [1@].
  • Vitamin C may enhance iron absorption, but the evidence supporting its effectiveness is mixed [3@].
  • Certain dietary manipulations, such as taking iron with ascorbic acid on an empty stomach, may improve iron absorption [3@].
  • Tea and coffee should be avoided within an hour after taking iron, as they can inhibit iron absorption [3@].

Administration and Monitoring

  • Ferrous sulfate should be taken on an empty stomach, 1 hour before or 2 hours after meals, with a full glass of water or orange juice to enhance absorption.
  • Common side effects of ferrous sulfate include constipation, black stools, nausea, and stomach discomfort.
  • Treatment typically continues for 3-6 months to replenish iron stores even after hemoglobin normalizes.
  • Patients who do not respond to oral iron supplementation may require further evaluation for nonadherence, malabsorption, or ongoing blood loss [4

From the FDA Drug Label

16 HOW SUPPLIED Ferrous Sulfate Tablets are available as follows: 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.

The appropriate dosing for ferrous sulfate (Iron Supplement) is not explicitly stated in the provided text, but it can be inferred that the recommended daily intake is met with 65mg of elemental iron, which is contained in one tablet of 324mg of ferrous sulfate 1.

  • The dosage is 65mg of elemental iron per tablet.
  • This provides 362% of the U.S. recommended daily intake (RDI) of iron for adults and children 4 and older.

From the Research

Dosing for Ferrous Sulfate (Iron Supplement)

The appropriate dosing for ferrous sulfate (iron supplement) can vary depending on the individual and the specific condition being treated.

  • For infants and children with nutritional iron-deficiency anemia, a dose of 3 mg/kg of elemental iron once daily as ferrous sulfate drops has been shown to be effective in increasing hemoglobin concentration 2.
  • In another study, children with iron deficiency anemia were given elemental iron in three divided doses of 6 mg/kg/day, with ferrous sulfate showing a better clinical response and fewer adverse effects compared to iron polymaltose complex 3.
  • A study in rural Ghana found that a single daily dose of 40 mg elemental iron as ferrous sulfate drops was as effective as a 3-times-daily dose in treating anemia in infants 4.
  • In adults with iron deficiency anemia, a daily dose of 60 mg elemental iron as ferrous sulfate was compared to an alternate day dose of 120 mg elemental iron, with no significant difference in hemoglobin increase between the two groups 5.
  • Another study found that lower therapeutic doses of iron (80 mg elemental iron) were equally effective as higher doses (200 mg elemental iron) in treating iron deficiency anemia, with ferrous sulfate and iron protein succinylate showing similar efficacy 6.

Key Findings

  • Ferrous sulfate is an effective treatment for iron deficiency anemia in both children and adults.
  • The optimal dosing strategy for ferrous sulfate may vary depending on the individual and the specific condition being treated.
  • Lower therapeutic doses of iron may be sufficient for managing iron deficiency anemia, with fewer gastrointestinal side effects.
  • Ferrous sulfate has been shown to be as effective as other iron supplements, such as iron polymaltose complex and iron protein succinylate, in treating iron deficiency anemia.

Professional Medical Disclaimer

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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