Drug interactions
Diclofenac + Fluorouracil
Severity: Moderate
Diclofenac and Fluorouracil: 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
Systemic fluorouracil has been linked to reduced CYP2C9 activity, which could raise diclofenac exposure. The evidence is limited, but both drugs can independently cause GI toxicity and myelosuppression-related bleeding risk.
What this interaction means in plain words
Diclofenac and Fluorouracil 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.
Diclofenac belongs to Musculoskeletal; Fluorouracil belongs to Oncology.
Why it happens
Possible reduction of CYP2C9-mediated diclofenac metabolism by fluorouracil, plus additive GI toxicity.
What to do
Monitor for GI bleeding, renal function and platelet counts during chemotherapy. Prefer a non-NSAID analgesic or the lowest effective diclofenac dose.
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 Diclofenac
- Diclofenac + Ketorolac Contraindicated
- Diclofenac + Ketorolac intranasal Contraindicated
- Aceclofenac + Diclofenac Major
- Acemetacin + Diclofenac Major
- Alteplase + Diclofenac Major
- Amiloride + Diclofenac Major
Other interactions of Fluorouracil
Frequently asked questions
Can I take Diclofenac with Fluorouracil?
MediHelp rates the interaction as moderate. Diclofenac and Fluorouracil 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. Systemic fluorouracil has been linked to reduced CYP2C9 activity, which could raise diclofenac exposure. The evidence is limited, but both drugs can independently cause GI toxicity and myelosuppression-related bleeding risk.
How serious is the interaction between Diclofenac and Fluorouracil?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for GI bleeding, renal function and platelet counts during chemotherapy. Prefer a non-NSAID analgesic or the lowest effective diclofenac dose.
What other medicines interact with Diclofenac?
MediHelp also lists interactions of Diclofenac with, for example, Ketorolac, Ketorolac intranasal, Aceclofenac. The full list is on the Diclofenac page.
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