Drug interactions
Ferrous fumarate + Sodium picosulfate / magnesium oxide / anhydrous citric acid
Severity: Moderate
Ferrous fumarate and Sodium picosulfate / magnesium oxide / anhydrous citric acid: 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
The bowel preparation produces magnesium citrate, a divalent cation that can bind iron in the gut and lower its absorption. The laxative effect also shortens intestinal transit, reducing the time available for iron absorption.
What this interaction means in plain words
Ferrous fumarate and Sodium picosulfate / magnesium oxide / anhydrous citric acid 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 iron by magnesium and citrate in the gastrointestinal tract together with accelerated transit reduces absorption.
What to do
Take oral iron at least 2 hours before and at least 6 hours after the bowel preparation. Oral iron is often withheld in the days before colonoscopy per local protocol.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Ferrous fumarate and Sodium picosulfate / magnesium oxide / anhydrous citric acid, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 14 days on the web. No card needed.
Other interactions of Ferrous fumarate
Frequently asked questions
Can I take Ferrous fumarate with Sodium picosulfate / magnesium oxide / anhydrous citric acid?
MediHelp rates the interaction as moderate. Ferrous fumarate and Sodium picosulfate / magnesium oxide / anhydrous citric acid 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. The bowel preparation produces magnesium citrate, a divalent cation that can bind iron in the gut and lower its absorption. The laxative effect also shortens intestinal transit, reducing the time available for iron absorption.
How serious is the interaction between Ferrous fumarate and Sodium picosulfate / magnesium oxide / anhydrous citric acid?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Take oral iron at least 2 hours before and at least 6 hours after the bowel preparation. Oral iron is often withheld in the days before colonoscopy per local protocol.
What other medicines interact with Ferrous fumarate?
MediHelp also lists interactions of Ferrous fumarate with, for example, Ciprofloxacin, Acetohydroxamic acid, Aluminum hydroxide. The full list is on the Ferrous fumarate page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
