Pharmacology of Anticoagulants, Antiplatelet Drugs, Coagulations & Thrombolytics

Question 1

What receptor is responsible for platelet-platelet binding?

Answer 1

GpIIb/IIIa

Question 2

What class of anticlotting drugs is most useful in treating areterial thromboses?

Answer 2

Antiplatelets

Question 3

True/False. All indirect thrombin inhibitors are approved for use during pregnancy.

Answer 3

False - only heparin is approved for pregnancy. Fondaparinux is not

Question 4

These drugs are used to treat life-threatening pulmonary emboli, severe deep vein thrombosis, and acute ischemic stroke.

Answer 4

Recombinant tPA - alteplase, reteplace, teneteplase

Question 5

What are the only classes of anticlotting drugs that dissolves existing clots?

Answer 5

Fibrinolytics and thrombolytics

Question 6

True/False. Aspirin is indicated for primary prevention of heart attack or stroke.

Answer 6

False - no evidence supports aspirin as a primary preventative. Evidence does support use to prevent another heart attack or stroke

Question 7

How does the MOA of Fondaparinux differ from heparin?

Answer 7

Both are indirect thrombin inhibitors, but Fondaparinux only enhances antithrombin’s ability to inactive Factor X and not thrombin directly

Question 8

Antifibrinolytics inhibt the activity of plasminogen activators. What drugs belong to this class?

Answer 8

Aminocaproic acid, tranexamic acid

Question 9

What clotting factors require Vitamin K for activation?

Answer 9

Factors II, VII, IX, X, Proteins C & S

Question 10

What anticoagulants are direct Factor X inhibitors?

Answer 10

Rivaroxaban, apixaban, edoxaban

Question 11

A PT test monitors the anticoagulation of what drug?

Answer 11

Warfarin

Question 12

To what drug class do dipyridamole and cilostazol belong? What is their MOA?

Answer 12

Phosphodiesterase inhibitors - increase platelet cAMP, which inhibits platelet aggregation by modifying the ADP P2Y12 receptor

Question 13

What is the antidote for heparin toxicity?

Answer 13

Protamine sulfate

Question 14

What indirect thrombin inhibitors are contraindicated in patients with renal failure?

Answer 14

Low molecular weight heparin, fondaparinux

Question 15

What are the classes of antiplatelet drugs?

Answer 15

COX inhibitors, Phosphodiesterase inhibitors, P2Y12 receptor blockers, GpIIb/IIIa receptor blockers, PAR antagonists

Question 16

What is the reversal agent for dabigatran?

Answer 16

Idarucizumab

Question 17

P2Y12 receptor blockers irreversibly inhibit ADP binding to the receptor. What drugs belong to this class?

Answer 17

Ticlopidine, clopidogrel, prasugrel

Question 18

What molecules are released by active platelets to enhance aggregation and vasoconstriction?

Answer 18

ADP, TXA2, serotonin

Question 19

This molecule naturally exists in the body to inhibit factors II, IX, X, XI, XII

Answer 19

Antithrombin III

Question 20

What antiplatelet drugs act by blocking the GpIIb/IIIa receptors?

Answer 20

Abciximab, eptifibatide, tirofiban

Question 21

True/False. Direct thrombin inhibitors bind free and clot-bound thrombin

Answer 21

True

Question 22

What is the primary contraindication of warfarin?

Answer 22

Pregnancy

Question 23

True/False. Warfarin is indicated to treat acute clots.

Answer 23

False - warfarin takes 4-5 days to become fully active. It is used as a preventative agent, not a curative agent

Question 24

What drugs are used to treat heparin-induced thrombocytopenia?

Answer 24

Direct thrombin inhibitors (bivalirudin, argatroban, dabigatran)

Question 25

This is a serious, but life-threatening ADR of heparin?

Answer 25

Heparin-induced thrombocytopenia

Question 26

How do the MOAs of warfarin and direct factor X inhibitors differ?

Answer 26

Warfarin inhibits the Vitamin K epoxide reductase, which when active, activates certain clotting factors that go on to activate Factor X. Direct Factor X inhibitors directly inhibit the activity of free and clot-bound Factor X

Question 27

What is the MOA of aspirin?

Answer 27

Irreversibly inhibits COX 1 & 2 to decrease production of TXA2 (thromboxane)

Question 28

What is the reversal agent for the direct factor X inhibitors?

Answer 28

Andexanet alpha

Question 29

This antifibrinolytic is used to treat heavy menstrual bleeding.

Answer 29

Tranexamic acid

Question 30

What is the MOA of heparin?

Answer 30

Heparin is an anticoagulant that indirectly inhibits thrombin by binding to antithrombin III and enhancing its functioning

Question 31

This anticoagulant is a Vitamin K antagonist.

Answer 31

Warfarin

Question 32

Clopidogrel is a prodrug that requires activation via liver metabolism. What enzyme is responsible for this transformation?

Answer 32

CYP2C19

Question 33

What drugs are recombinant tPA?

Answer 33

Alteplase, reteplace, teneteplase

Question 34

CYP2C9 is important in the metabolism of what anticoagulant?

Answer 34

Warfarin

Question 35

These drugs reversibly inhibit COX 1 & 2 to inhibit TXA2 production.

Answer 35

NSAIDs

Question 36

What are the three classes of anticlotting drugs?

Answer 36

Antiplatelets, anticoagulants and thrombolytics, fibrinolytics

Question 37

What is the only antiplatelet drug that is a reversible antagonist of the P2Y12 receptor and its primary side effect?

Answer 37

Ticagrelor, shortness of breath

Question 38

What test can be used to monitor heparin anticoagulation?

Answer 38

PTT

Question 39

What are the direct thrombin inhibitors?

Answer 39

Hirudin, bivalirudin, argatroban, dabigatran

Question 40

What primary ADR is associated with abciximab, eptifibatide, and tirofiban?

Answer 40

These are antiplatelet drugs -GpIIb/IIIa blockers. Primary ADR is thrombocytopenia

Question 41

Early in administration, warfarin creates a hypercoagulable state that increases the risk of warfarin-induced skin necrosis due to clots. Explain the pathophysiology.

Answer 41

Warfarin inactivates protein C. Protein C functions as an inactivator of several clotting factors. Early inactivation of Protein C increases the risk of coagulation before warfarin's anticoagulant effect is fully achieved

Question 42

What is a contraindication for cilostazol use?

Answer 42

Congestive heart failure

Question 43

What is the MOA of fibrinolytics?

Answer 43

Activate plasminogen to plasmin to breakdown fibrin clots

Question 44

What is the MOA of vorapaxar?

Answer 44

Antiplatelet - competitive antagonist of the PAR receptor to prevent thrombin from binding platelets

Question 45

What are the clinical indications for dabigatran?

Answer 45

Prevent venous thrombosis post-surgery, atrial fibrillation

Question 46

This drug is used to prepare patients with hemophilia or vWF disease for elective surgery.

Answer 46

Desmopressin

Question 47

True/False. Heparin only affects free thrombin and Factor X.

Answer 47

True - heparin has no effect on clot-bound thrombin or Factor X

Question 48

This test is used to assess platelet functioning.

Answer 48

Bleeding time

Question 49

This drug stabilizes and increases the activity of Factor VIII and vWF.

Answer 49

Desmopressin