Drug interactions
Calcium carbonate + Ferrous fumarate
Severity: Moderate
Calcium carbonate and Ferrous fumarate: 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
Calcium carbonate lowers the absorption of oral iron salts. This can blunt the response to iron therapy in iron deficiency.
What this interaction means in plain words
Calcium carbonate and Ferrous fumarate 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.
Calcium carbonate belongs to Gastrointestinal Tract; Ferrous fumarate belongs to Miscellaneous.
Why it happens
Calcium competes with iron for intestinal uptake and raises gastric pH, which reduces solubility of non-heme iron.
What to do
Separate doses by at least 2 hours and take iron apart from calcium-containing meals; monitor hemoglobin and ferritin.
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 Calcium carbonate
Other interactions of Ferrous fumarate
Frequently asked questions
Can I take Calcium carbonate with Ferrous fumarate?
MediHelp rates the interaction as moderate. Calcium carbonate and Ferrous fumarate 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. Calcium carbonate lowers the absorption of oral iron salts. This can blunt the response to iron therapy in iron deficiency.
How serious is the interaction between Calcium carbonate and Ferrous fumarate?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Separate doses by at least 2 hours and take iron apart from calcium-containing meals; monitor hemoglobin and ferritin.
What other medicines interact with Calcium carbonate?
MediHelp also lists interactions of Calcium carbonate with, for example, Acalabrutinib, Alendronate, Amlodipine-hydrochlorothiazide-valsartan. The full list is on the Calcium carbonate page.
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