Which medication could increase the risk of bleeding when taken with warfarin?

The choice indicating both Aspirin and Ibuprofen as increasing the risk of bleeding when taken with warfarin is correct due to the antiplatelet and anti-inflammatory properties of these medications.

Aspirin acts as an antiplatelet agent by irreversibly inhibiting cyclooxygenase (COX) enzymes, which leads to reduced thromboxane A2 production, a substance that promotes platelet aggregation. This effect can potentiate the anticoagulant effects of warfarin, thereby increasing the risk of bleeding complications.

Ibuprofen, a nonsteroidal anti-inflammatory drug (NSAID), can also interfere with platelet function and may disrupt the gastric mucosal barrier, leading to gastrointestinal bleeding. It can interact with warfarin by displacing it from protein-binding sites and affecting renal function, further raising the bleeding risk.

While acetaminophen is generally considered safer in terms of bleeding risk when used with warfarin, it does not possess the same antiplatelet or mucosal irritant properties that increase bleeding potential. Therefore, the combination of both Aspirin and Ibuprofen with warfarin warrants caution due to the enhanced risk of bleeding.