Drug interactions
Iron + Tetracycline
Severity: Moderate
Iron 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 markedly reduces tetracycline absorption, and tetracycline may also lower iron absorption. This can result in subtherapeutic antibiotic levels.
What this interaction means in plain words
Iron 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.
Iron belongs to Gastrointestinal Tract; Tetracycline belongs to Anti Bacterial.
Why it happens
Chelation of tetracycline by iron in the gut, forming poorly absorbed complexes.
What to do
Separate doses by at least 2 to 3 hours, giving tetracycline first. Intravenous iron avoids the interaction.
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 Iron
- Acetohydroxamic acid + Iron Moderate
- Aluminum hydroxide + Iron Moderate
- Baloxavir marboxil + Iron Moderate
- Calcium acetate + Iron Moderate
- Calcium carbonate + Iron Moderate
- Calcium citrate + Iron Moderate
Other interactions of Tetracycline
- Acitretin + Tetracycline Contraindicated
- Methoxyflurane + Tetracycline Contraindicated
- Isotretinoin + Tetracycline Major
- Palovarotene + Tetracycline Major
- Strontium ranelate + Tetracycline Major
- Tetracycline + Tretinoin Major
Frequently asked questions
Can I take Iron with Tetracycline?
MediHelp rates the interaction as moderate. Iron 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 markedly reduces tetracycline absorption, and tetracycline may also lower iron absorption. This can result in subtherapeutic antibiotic levels.
How serious is the interaction between Iron 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: Separate doses by at least 2 to 3 hours, giving tetracycline first. Intravenous iron avoids the interaction.
What other medicines interact with Iron?
MediHelp also lists interactions of Iron with, for example, Acetohydroxamic acid, Aluminum hydroxide, Baloxavir marboxil. The full list is on the Iron page.
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