Iron reduces levothyroxine absorption
Iron forms insoluble complexes with levothyroxine, reducing absorption significantly. Can cause treatment failure and persistent hypothyroid symptoms.
Take thyroid medication 4+ hours before iron supplements.
Thyroid med in morning, iron in evening
Iron reduces levothyroxine absorption. Take thyroid medication 4+ hours before iron supplements.
Thyroid med in morning, iron in evening
This interaction is rated “Warning” by Formulate. Iron forms insoluble complexes with levothyroxine, reducing absorption significantly. Can cause treatment failure and persistent hypothyroid symptoms.
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Medical disclaimer. This page is for educational purposes only and does not replace advice from a qualified healthcare provider.