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Medicines ferrous sulfateQuestion & answer

ferrous sulfate · Medicine question

How does ferrous sulfate affect the absorption of levothyroxine?

iatroX medicinesPublished 8 November 2026

The answer

Answer

Ferrous sulfate reduces levothyroxine absorption, so the medicines should be taken at least 2 hours apart.

Sources for this answer

Ferrous Sulfate 200mg Coated TabletsWockhardt UK Ltd · emc · SmPC §4.5 Interaction with other medicinal products · Version 7Document updated 15 January 2026

Sources checked 8 November 2026

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More questions about ferrous sulfate

Can prolonged use of ferrous sulfate cause constipation and faecal impaction in older patients?Does the Sandoz Limited product Ferrous Sulfate Tablets 200mg contain sucrose?Is ferrous sulfate contraindicated in people with haemochromatosis or other iron overload syndromes?What restriction applies to using Ironorm Drops containing ferrous sulfate during the first trimester of pregnancy?What type of anaemia is ferrous sulfate used to treat?

ferrous sulfate

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