Drug interactions
Magnesium oxide + Nitrofurantoin
Severity: Minor
Magnesium oxide and Nitrofurantoin: minor 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-containing antacids can reduce nitrofurantoin absorption, potentially lowering urinary concentrations and efficacy. Magnesium trisilicate is the best documented, and the effect with magnesium oxide is extrapolated.
What this interaction means in plain words
Magnesium oxide and Nitrofurantoin have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Magnesium oxide belongs to Gastrointestinal Tract; Nitrofurantoin belongs to Anti Bacterial.
Why it happens
Magnesium binds or adsorbs nitrofurantoin in the gastrointestinal tract, decreasing absorption.
What to do
Give nitrofurantoin at least 2 hours before magnesium oxide. Assess clinical response if the urinary infection does not improve.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Nitrofurantoin
Other interactions of Magnesium oxide
- Chloroquine + Magnesium oxide Moderate
- Ciprofloxacin + Magnesium oxide Moderate
- Dolutegravir + Magnesium oxide Moderate
- Doxycycline + Magnesium oxide Moderate
- Eltrombopag + Magnesium oxide Moderate
- Gemifloxacin + Magnesium oxide Moderate
Frequently asked questions
Can I take Magnesium oxide with Nitrofurantoin?
MediHelp rates the interaction as minor. Magnesium oxide and Nitrofurantoin have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Oral magnesium-containing antacids can reduce nitrofurantoin absorption, potentially lowering urinary concentrations and efficacy. Magnesium trisilicate is the best documented, and the effect with magnesium oxide is extrapolated.
How serious is the interaction between Magnesium oxide and Nitrofurantoin?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Give nitrofurantoin at least 2 hours before magnesium oxide. Assess clinical response if the urinary infection does not improve.
What other medicines interact with Nitrofurantoin?
MediHelp also lists interactions of Nitrofurantoin with, for example, Pexidartinib, Pretomanid, Aluminum hydroxide. The full list is on the Nitrofurantoin page.
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