Iron Sulfate and Levothyroxine: Drug Interaction Guide

Quick answer: This combination requires caution. Iron Sulfate and Levothyroxine can be used together with adjustments and monitoring.

Interaction severity: Moderate — caution required

How Iron Sulfate interacts with Levothyroxine

Iron forms insoluble chelates with levothyroxine in the gastrointestinal tract, reducing thyroxine absorption by up to 30%.

What you should do

Separate administration by at least 4 hours and recheck TSH 6-8 weeks after initiating iron therapy.

Key facts

Severity

Moderate — caution required

Mechanism

Iron forms insoluble chelates with levothyroxine in the gastrointestinal tract, reducing thyroxine absorption by up to 3...

Action

Separate administration by at least 4 hours and recheck TSH 6-8 weeks after initiating iron therapy.

Important medical disclaimer: This page provides educational information about drug interactions for general reference. It is not a substitute for professional medical advice, diagnosis, or treatment. Always discuss your specific medications with a qualified healthcare provider before starting, stopping, or changing any treatment. About our editorial team.

Frequently asked questions

Can I take Iron Sulfate and Levothyroxine together?

With caution. Separate administration by at least 4 hours and recheck TSH 6-8 weeks after initiating iron therapy.

What is the severity of this interaction?

The interaction between Iron Sulfate and Levothyroxine is classified as Moderate — caution required. Iron forms insoluble chelates with levothyroxine in the gastrointestinal tract, reducing thyroxine absorption by up to 30%.

What should I do if I'm prescribed both?

Separate administration by at least 4 hours and recheck TSH 6-8 weeks after initiating iron therapy. Always consult your prescribing clinician — do not stop or change medications without medical guidance.

Last reviewed: by iMedic Medical Editorial Team. Our editorial process.