Drug interactions
Diflunisal + Sulfamethoxazole
Severity: Minor
Diflunisal and Sulfamethoxazole: minor 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
Diflunisal is highly protein bound and may displace sulfonamides or compete for renal secretion, potentially raising sulfamethoxazole exposure. NSAIDs can also reduce renal function, which matters with this antibiotic. Clinical significance is uncertain.
What this interaction means in plain words
Diflunisal and Sulfamethoxazole have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Why it happens
Possible protein-binding displacement and competition for renal tubular secretion; mechanism not firmly established.
What to do
Monitor renal function and potassium in at-risk patients and watch for sulfonamide adverse effects.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Diflunisal
- Diflunisal + Ketorolac Contraindicated
- Diflunisal + Ketorolac intranasal Contraindicated
- Acemetacin + Diflunisal Major
- Acetazolamide + Diflunisal Major
- Alteplase + Diflunisal Major
- Amiloride + Diflunisal Major
Frequently asked questions
Can I take Diflunisal with Sulfamethoxazole?
MediHelp rates the interaction as minor. Diflunisal and Sulfamethoxazole have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Diflunisal is highly protein bound and may displace sulfonamides or compete for renal secretion, potentially raising sulfamethoxazole exposure. NSAIDs can also reduce renal function, which matters with this antibiotic. Clinical significance is uncertain.
How serious is the interaction between Diflunisal and Sulfamethoxazole?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor renal function and potassium in at-risk patients and watch for sulfonamide adverse effects.
What other medicines interact with Diflunisal?
MediHelp also lists interactions of Diflunisal with, for example, Ketorolac, Ketorolac intranasal, Acemetacin. The full list is on the Diflunisal page.
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