Acetaminophen and ibuprofen and Diflunisal interaction
Acetaminophen and ibuprofen and Diflunisal: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Diflunisal label · effective 2026-08-04
Diflunisal tablets should not be given to patients who have experienced asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs.
This symptom complex typically occurs in asthmatic patients who experience rhinitis with or without nasal polyps, or who exhibit severe, potentially fatal bronchospasm after taking aspirin or other NSAIDs (see CONTRAINDICATIONS and PRECAUTIONS, Preexisting Asthma ).
The concomitant use of diflunisal tablets and other NSAIDs is not recommended due to the increased possibility of gastrointestinal toxicity, with little or no increase in efficacy.
Acetaminophen In normal volunteers, concomitant administration of diflunisal and acetaminophen resulted in an approximate 50% increase in plasma levels of acetaminophen.
Since acetaminophen in high doses has been associated with hepatotoxicity, concomitant administration of diflunisal tablets and acetaminophen should be used cautiously, with careful monitoring of patients.
From the Acetaminophen and ibuprofen (Combogesic) label · effective 2026-08-20
COMBOGESIC is contraindicated in: • patients with a known hypersensitivity (e.g., anaphylactic reactions, serious skin reactions) to acetaminophen, ibuprofen, other NSAIDs, or to any of the excipients in this product [see Warnings and Precautions (5.7 , 5.8 , 5.9) ].
• patients with a history of asthma, urticaria, or other allergic-type reactions after taking aspirin or other NSAIDS [see Warnings and Precautions (5.7 and 5.8) ] .
COMBOGESIC is contraindicated in: • patients with known hypersensitivity to acetaminophen, ibuprofen, other NSAIDs, or to any of the excipients in this product ( 4 ).
• patients with a history of asthma, urticaria, or other allergic-type reactions after taking aspirin or other NSAIDs.
• Avoid administration of more than one NSAID at a time.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.