Does Magnesium Trisilicate Interact with Nitrofurantoin?
Magnesium Trisilicate and Nitrofurantoin have a moderate drug interaction according to U.S. FDA drug labeling data. Antacids containing magnesium trisilicate reduce both rate and extent of nitrofurantoin absorption. Monitor for lack of efficacy. The mechanism involves adsorption of nitrofurantoin onto the surface of magnesium trisilicate. Patients taking both medications should consult their healthcare provider before starting, stopping, or changing the dosage of either drug. This information is based on official FDA drug labeling sourced from OpenFDA and the NIH National Library of Medicine.
- Severity
- Moderate
- Nitrofurantoin Class
- Nitrofuran Antibacterial
- Management
- Monitor for effects
- Data Source
- U.S. FDA via OpenFDA
How This Interaction Works
The interaction between Magnesium Trisilicate and Nitrofurantoin occurs because adsorption of nitrofurantoin onto the surface of magnesium trisilicate. Clinically, this means antacids containing magnesium trisilicate reduce both rate and extent of nitrofurantoin absorption. monitor for lack of efficacy. This is classified as a moderate interaction. While it may not require stopping either medication, your healthcare provider should be aware you are taking both so they can monitor for potential effects and adjust treatment if necessary.
What To Tell Your Doctor or Pharmacist
If you are taking Magnesium Trisilicate and your doctor is considering prescribing Nitrofurantoin (or vice versa), make sure to:
- Inform your doctor and pharmacist of all current medications, including over-the-counter drugs and supplements
- Ask whether the benefits of combining these medications outweigh the risks for your specific situation
- Ask what symptoms to watch for that would indicate the interaction is causing problems
- Ask whether any dosage adjustments are needed
- Never stop or change either medication without first consulting your healthcare provider