Acetaminophen and Diflunisal Interaction

Drug interaction information between Acetaminophen and Diflunisal.

Acetaminophen and Diflunisal have a documented minor interaction in FDA labeling.

FDA drug labeling documents a minor-severity interaction between Acetaminophen and Diflunisal. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.

Drug A

Acetaminophen

Analgesic / Antipyretic

Drug B

Diflunisal

Nonsteroidal Anti-Inflammatory Drug (NSAID)

How They Interact

Diflunisal causes the levels of acetaminophen in your blood to go up by about half. This could increase the risk of liver damage from the acetaminophen.

FDA Label Information

Acetaminophen In normal volunteers, concomitant administration of diflunisal and acetaminophen resulted in an approximate 50% increase in plasma levels of acetaminophen. Acetaminophen had no effect on plasma levels of diflunisal. 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.

Frequently Asked Questions

What SPL severity band is on file for Acetaminophen + Diflunisal?

Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.

Which drug in this pair has the larger labeled-interaction portfolio?

Acetaminophen has 23 labeled pairs on file vs Diflunisal's 17. In the minor band specifically: Acetaminophen has 21 (also Acetaminophen/Oxycodone, Carbamazepine, Cidofovir, Codeine); Diflunisal has 6 (also Hydrochlorothiazide, Furosemide, Aspirin, Lithium).

What mechanism field is on file for Acetaminophen and Diflunisal?

Diflunisal causes the levels of acetaminophen in your blood to go up by about half. This could increase the risk of liver damage from the acetaminophen.

Acetaminophen's labeled portfolio outnumbers Diflunisal

SPL source-record counts only. This page's band is minor · classes on file: Acetaminophen (Analgesic / Antipyretic); Diflunisal (Nonsteroidal Anti-Inflammatory Drug (NSAID)).

Acetaminophen

0 major · 2 moderate · 21 minor · 23 total

Diflunisal

0 major · 11 moderate · 6 minor · 17 total

Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.