Drug interactions
Magnesium sulfate + Tetracycline
Severity: Moderate
Magnesium sulfate 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 sulfate can bind oral tetracycline in the gut and reduce its absorption. Parenteral magnesium sulfate would not have this effect.
What this interaction means in plain words
Magnesium sulfate 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.
Why it happens
Chelation of tetracycline by magnesium cations in the gastrointestinal tract reduces absorption.
What to do
If oral magnesium sulfate is used, give tetracycline at least 2 hours before or 4 hours after it. Parenteral magnesium needs no separation.
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 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 sulfate with Tetracycline?
MediHelp rates the interaction as moderate. Magnesium sulfate 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 sulfate can bind oral tetracycline in the gut and reduce its absorption. Parenteral magnesium sulfate would not have this effect.
How serious is the interaction between Magnesium sulfate 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: If oral magnesium sulfate is used, give tetracycline at least 2 hours before or 4 hours after it. Parenteral magnesium needs no separation.
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.
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