Drug interactions
Ferrous fumarate + Tetracycline
Severity: Moderate
Ferrous fumarate and Tetracycline: 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
Oral iron binds tetracycline in the gut, forming poorly absorbed complexes. This lowers tetracycline blood levels and can lead to treatment failure.
What this interaction means in plain words
Ferrous fumarate and Tetracycline 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; Tetracycline belongs to Anti Bacterial.
Why it happens
Chelation of tetracycline by ferrous iron in the gastrointestinal tract, reducing absorption.
What to do
Give oral tetracycline at least 2 hours before or 3 to 4 hours after the iron preparation. Separating the doses avoids the need to stop either drug.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Ferrous fumarate and Tetracycline, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 14 days on the web. No card needed.
Other interactions of Tetracycline
- Acitretin + Tetracycline Contraindicated
- Methoxyflurane + Tetracycline Contraindicated
- Isotretinoin + Tetracycline Major
- Palovarotene + Tetracycline Major
- Strontium ranelate + Tetracycline Major
- Tetracycline + Tretinoin Major
Other interactions of Ferrous fumarate
Frequently asked questions
Can I take Ferrous fumarate with Tetracycline?
MediHelp rates the interaction as moderate. Ferrous fumarate and Tetracycline 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. Oral iron binds tetracycline in the gut, forming poorly absorbed complexes. This lowers tetracycline blood levels and can lead to treatment failure.
How serious is the interaction between Ferrous fumarate and Tetracycline?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Give oral tetracycline at least 2 hours before or 3 to 4 hours after the iron preparation. Separating the doses avoids the need to stop either drug.
What other medicines interact with Tetracycline?
MediHelp also lists interactions of Tetracycline with, for example, Acitretin, Methoxyflurane, Isotretinoin. The full list is on the Tetracycline page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
