Drug interactions
Magnesium + Tetracycline
Severity: Moderate
Magnesium 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 magnesium markedly decreases tetracycline absorption, which can lead to subtherapeutic antibiotic concentrations and failure of therapy.
What this interaction means in plain words
Magnesium 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.
Magnesium belongs to Gastrointestinal Tract; Tetracycline belongs to Anti Bacterial.
Why it happens
Magnesium cations chelate tetracycline in the gut, forming insoluble complexes that are poorly absorbed.
What to do
Give tetracycline at least 2 hours before or 4 hours after magnesium-containing products. Use an alternative antibiotic if separation is not feasible.
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 Magnesium
- Ciprofloxacin + Magnesium Major
- Magnesium + Pancuronium Major
- Magnesium + Rocuronium Major
- Magnesium + Vecuronium Major
- Amikacin + Magnesium Moderate
- Amphotericin b deoxycholate + Magnesium 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 Magnesium with Tetracycline?
MediHelp rates the interaction as moderate. Magnesium 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 magnesium markedly decreases tetracycline absorption, which can lead to subtherapeutic antibiotic concentrations and failure of therapy.
How serious is the interaction between Magnesium 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 tetracycline at least 2 hours before or 4 hours after magnesium-containing products. Use an alternative antibiotic if separation is not feasible.
What other medicines interact with Magnesium?
MediHelp also lists interactions of Magnesium with, for example, Ciprofloxacin, Pancuronium, Rocuronium. The full list is on the Magnesium page.
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