Drug interactions
Ferrous fumarate + Liothyronine
Severity: Moderate
Ferrous fumarate and Liothyronine: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Iron binds thyroid hormone in the gut and can reduce its absorption. This may lead to hypothyroid symptoms or a raised TSH.
What this interaction means in plain words
Ferrous fumarate and Liothyronine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Ferrous fumarate belongs to Miscellaneous; Liothyronine belongs to Endocrine.
Why it happens
Iron forms insoluble complexes with thyroid hormone in the gut, reducing absorption.
What to do
Separate doses by at least 4 hours. Check TSH after starting or changing iron.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Ferrous fumarate
Other interactions of Liothyronine
- Alogliptin-metformin + Liothyronine Moderate
- Amitriptyline + Liothyronine Moderate
- Amobarbital + Liothyronine Moderate
- Canagliflozin-metformin + Liothyronine Moderate
- Carbamazepine + Liothyronine Moderate
- Carbonyl iron + Liothyronine Moderate
Frequently asked questions
Can I take Ferrous fumarate with Liothyronine?
MediHelp rates the interaction as moderate. Ferrous fumarate and Liothyronine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Iron binds thyroid hormone in the gut and can reduce its absorption. This may lead to hypothyroid symptoms or a raised TSH.
How serious is the interaction between Ferrous fumarate and Liothyronine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Separate doses by at least 4 hours. Check TSH after starting or changing iron.
What other medicines interact with Ferrous fumarate?
MediHelp also lists interactions of Ferrous fumarate with, for example, Ciprofloxacin, Acetohydroxamic acid, Aluminum hydroxide. The full list is on the Ferrous fumarate page.
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