In what century is this question taking place?? Dicoumarol was replaced by warfarin in the mid-1950s! It's on the FDA's list of discontinued drug products!

From wikipedia: "Identified in 1940, dicoumarol became the prototype of the 4-hydroxycoumarin anticoagulant drug class. Dicoumarol itself, for a short time, was employed as a medicinal anticoagulant drug, but since the mid-1950s has been replaced by its simpler derivative warfarin, and other 4-hydroxycoumarin drugs."

Did the grandpa have some leftover dicoumarol in the cabinet from his DVT in the summer of 1949?? This question is absolutely ridiculous.

https://en.wikipedia.org/wiki/Dicoumarol https://pubchem.ncbi.nlm.nih.gov/compound/Dicumarol#section=Uses

Dicumarol is in the coumarin family which includes warfarin. It helps if you think about warfarin's brand name Coumadin. Coumadin, coumarin, dicumarol...all the other derivatives have COUM it in some fashion

You can basically think of Dicumarol as warfarin. MOA: Depletes vitamin K stores Since Vitamin K is involved in gamma carboxylation of factors 2, 7, 9, & 10, you can use the Prothrombin Time to measure the response. Prothrombin time measures the extrinsic pathway of coagulation, which is mainly mediated via Factor 7.

If you don't know what Dicumarol does like any normal human. The focus on what aspirin doesn't do, namely it's doesn't affect PT time and most pills don't increase clotting (especially with aspirin). This is how I logic to the right answer.

we need to know like 400 drugs in FA, and they choose the one that's not in there. thanks NBME