Anti coagulant drugs

Question 1

What are the names of anticoagulant drugs?

Answer 1

Warfarin

Heparin

Clopidogrel

ASA

Question 2

Describe mechanism of action for Warfarin

Answer 2

Warfarincompetitively inhibits the vitamin K epoxide reductase complex 1 (VKORC1), an
essential enzyme for activating the vitamin K available in the body. Through this mechanism,
warfarin can deplete functional vitamin K reserves and thereby reduce the synthesis of active
clotting factors.
 Inhibits synthesis of coagulation factors II (prothrombin), VII, IX and X
 Oral administration
 Hard drug to use: Several days before effect, many interactions with other drugs, narrow
therapeutic window, requires laboratory monitoring

Question 3

Heparin mechanism

Answer 3

Heparin, binds to the enzyme inhibitor Inhibits thrombin (factor IIa) and factor Xa by increasing the effect of antithrombin III (increasing
the affinity)
 Requires laboratory monitoring

Question 4

Clopidogrel mechanism

Answer 4

Clopidogrel The active metabolite of clopidogrel selectively inhibits the binding of adenosine diphosphate (ADP) to its platelet P2Y12 receptor and the subsequent ADP- mediated activation of the glycoprotein GPIIb/IIIa complex, thereby inhibiting platelet aggregation. This action is irreversible.

Question 5

ASA mechanism

Answer 5

Acetylsalicylic acid (ASA) partially and irreversibly inhibits collagen-induced platelet activation by blocking the activity of COX1 and COX2 but with higher affinity for COX 1.

COX enzymes make prostaglandins, and COX 1 makes H2 and TAX 2 which is a potent vasoconstrictor and platelet activation, aggregation and turns fibrinogen into fibrin is synthesized from H2.