Drug interactions
Diclofenac + Sulfadiazine
Severity: Moderate
Diclofenac and Sulfadiazine: 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
Sulfadiazine inhibits CYP2C9, the main enzyme that metabolizes diclofenac, which may raise diclofenac exposure and the risk of GI, renal and cardiovascular adverse effects. Both drugs can also affect the kidney.
What this interaction means in plain words
Diclofenac and Sulfadiazine 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
Inhibition of CYP2C9-mediated diclofenac metabolism by sulfadiazine.
What to do
Use the lowest effective diclofenac dose for the shortest time, and monitor renal function and for GI adverse effects. Ensure good hydration during sulfadiazine therapy.
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
Frequently asked questions
Can I take Diclofenac with Sulfadiazine?
MediHelp rates the interaction as moderate. Diclofenac and Sulfadiazine 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. Sulfadiazine inhibits CYP2C9, the main enzyme that metabolizes diclofenac, which may raise diclofenac exposure and the risk of GI, renal and cardiovascular adverse effects. Both drugs can also affect the kidney.
How serious is the interaction between Diclofenac and Sulfadiazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use the lowest effective diclofenac dose for the shortest time, and monitor renal function and for GI adverse effects. Ensure good hydration during sulfadiazine therapy.
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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