How many milligrams (mg) of elemental iron are in ferrous sulfate 200 mg?

Elemental Iron Content in Ferrous Sulfate 200 mg

Ferrous sulfate 200 mg contains 65 mg of elemental iron. 1

Standard Conversion

• Ferrous sulfate 200 mg tablets contain 65 mg of elemental iron, as clearly documented in the British Society of Gastroenterology guidelines 1
• This represents approximately 32.5% elemental iron content by weight 1
• The FDA drug label confirms that ferrous sulfate 324 mg contains 65 mg elemental iron, maintaining the same ratio 2

Clinical Context for Dosing

• One ferrous sulfate 200 mg tablet daily (providing 65 mg elemental iron) is recommended as the optimal starting dose for iron deficiency anemia treatment 1
• This once-daily dosing approach is preferred because doses of 60 mg elemental iron stimulate hepcidin levels, reducing subsequent iron absorption by 35-45% when taken multiple times daily 1
• The recommended therapeutic range is 50-100 mg elemental iron once daily, making a single 200 mg ferrous sulfate tablet (65 mg elemental iron) an ideal choice 1

Comparison with Other Formulations

• Ferrous sulfate 325 mg contains 105 mg elemental iron 1
• Ferrous fumarate 210 mg contains 69 mg elemental iron 1
• Ferrous gluconate 300 mg contains only 37 mg elemental iron 1

Important Prescribing Note

• When prescribing iron supplementation, always specify both the salt form (ferrous sulfate) and the dose (200 mg), as the elemental iron content varies significantly between different iron preparations 1