NSAIDs and warfarin

Q: Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) _______________ the effect of warfarin? (select one)

A) attenuates

B) enhances

Answer: B

Except for aspirin (ASA), all NSAIDs are highly protein bound. This phenomenon leads to the displacement of other protein-bound drugs like phenytoin or warfarin. 

Once warfarin is displaced, its serum level is increased, and so does the effect. 

#pharmacology

Reference:

Choi KH, Kim AJ, Son IJ, Kim KH, Kim KB, Ahn H, Lee EB. Risk factors of drug interaction between warfarin and nonsteroidal anti-inflammatory drugs in practical setting. J Korean Med Sci. 2010 Mar;25(3):337-41. doi: 10.3346/jkms.2010.25.3.337. Epub 2010 Feb 17. PMID: 20191029; PMCID: PMC2826747.