Aspirin:
1 ❏ potentiates the anticoagulant effect of warfarin
2 ❏ inhibits platelet aggregation
3 ❏ promotes vitamin K synthesis
ONE or MORE of the responses above is (are) correct. Decide which of the responses is
(are) correct. Then choose:
A ❏ if 1, 2 and 3 are correct
B ❏ if 1 and 2 only are correct
C ❏ if 2 and 3 only are correct
D ❏ if 1 only is correct
E ❏ if 3 only is correct
B is the answer, and Clement is the winner.
Details:
Because of its antiplatelet effect, the administration of aspirin to patients receiving warfarin is associated with a potentiated anticoagulant effect leading to
an increased risk of bleeding. Aspirin decreases platelet aggregation by
inactivating cyclo-oxygenase, an enzyme involved in the platelet aggregationpathway through the interference with thromboxane A2. Vitamin K is required
for the procoagulation activity. Aspirin does not interfere with vitamin K synthesis. However warfarin, which is an oral anticoagulant, acts as a vitamin K
antagonist.
B
B
B
A