Pharm: Anti Coag Anti Platelet

Question 1

When do we use antithrombotic therapy?

Answer 1

prevent thrombosis in pts w/acute or symptomatic venous thromboembolism

Question 2

3 subgroups of antithrombotic agents

Answer 2

anticoagulants
antiplatelet agents
fibrinolytic agents

Question 3

Venous thrombosis thrombi?

Answer 3

Red thrombi, RBCs enmeshed in thrombi

Question 4

Arterial thrombosis thrombi?

Answer 4

White thrombi, platelets with little fibrin or red cells

Question 5

Venous thrombosis risk factors?

Answer 5

immobility, surgery, cancer, pregnancy, estrogen use

Question 6

Arterial thrombosis risk factors?

Answer 6

smoking, HTN, DM, obesity, hyperlipidemia

Question 7

Gain of function mutations associated with venous thrombosis?

Answer 7

G20210A

factor V leiden

Question 8

What causes primary hemostasis?

Answer 8

formation of a platelet monolayer over the subendothelial matrix
platelets are held in place by vWF

Question 9

What receptor is necessary for platelet aggregation?

Answer 9

GPIIb/IIIa

Question 10

What do platelets synthesize from arachidonic acid?

Answer 10

TXA2

Question 11

What causes secondary hemostasis?

Answer 11

coagulation cascase (conversion of soluble fibrinogen to insoluble fibrin)
clot formation

Question 12

How to platelets activate the coagulation cascade?

Answer 12

surface phospholipids provide support on which the complexes of coag cascade are formed, allowing for calcium binding

Question 13

Heparin mechanism

Answer 13

no intrinsic anticoag activity
binds antithrombin and thrombin simultaneously
accelerates rate of interaction of antithrombin w/Xa

Question 14

Heparin admin

Answer 14

parenteral, immediate onset of action

Question 15

What are the LMWHs?

Answer 15

exoxaparin

dalteparin

Question 16

LMWH mechanism

Answer 16

potentiate factor Xa inhibition by antithrombin

not as good at inhibiting thrombin

Question 17

LMWH admin

Answer 17

parenteral, can accumulate in pts w/renal disease

Question 18

Heparin SEs

Answer 18

thrombocytopenia

bleeding

Question 19

LMWH SEs

Answer 19

bleeding

lower risk of thrombocytopenia

Question 20

What are the direct thrombin inhibitors?

Answer 20

lepirudin

bivalirudin

Question 21

Lepirudin mechanism?

Answer 21

binds tightly to catalytic site and extended substrate recognition site of thrombin

Question 22

Bivalirudin mechanism?

Answer 22

occupies catalytic site of thrombin

Question 23

Direct thrombin inhibitors admin?

Answer 23

parenteral

excreted by kidneys

Question 24

What is the direct factor Xa inhibitor?

Answer 24

Fondaparinux

Question 25

Fondaparinux mechanism?

Answer 25

causes antithrombin mediated selective inhibition of Xa

Question 26

Fondaparinux admin?

Answer 26

subcut | Do NOT use in pts w/renal failure

Question 27

Direct thrombin inhibitor SEs?

Answer 27

bleeding if they accumulate

Question 28

Fondaparinux SEs

Answer 28

bleeding | much less likely to cause thrombocytopenia

Question 29

Warfarin mechanism?

Answer 29

inhibits vitamin K epoxide, which recycles vit K back to it's active form

Question 30

What requires Vit K?

Answer 30

facotrs 2,7,9,10, protein C, protein S

Question 31

Which enantiomer of warfarin ia most active?

Answer 31

S

Question 32

What metabolizes warfarin?

Answer 32

CYP2C9

Question 33

Polymorphisms in which protein affects dosing?

Answer 33

VKORC1 | affects the susceptibility of hte enzyme to warfarin induced inhibition

Question 34

Warfarin SEs?

Answer 34

bleeding birth defects/abortion skin necrosis purple toe syndrome

Question 35

What is the oral direct thrombin inhibitor?

Answer 35

dabigatran

Question 36

Metab of dabigatran?

Answer 36

renal excretion

Question 37

What drug should NOT be administered with dabigatran?

Answer 37

rifampin | both are Pgp substrates

Question 38

Dabigatran SEs?

Answer 38

bleeding

Question 39

What is the orally available direct factor Xa inhibitor?

Answer 39

Rivaroxaban

Question 40

What does factor Xa do?

Answer 40

converts prothrombin to thrombin

Question 41

How is rivaroxaban eliminated?

Answer 41

unchanged by kidneys or metabolized by liver

Question 42

What are the thrombolytic agent?

Answer 42

alteplase

Question 43

Mechanism of alteplase?

Answer 43

plasminogen activator

Question 44

alteplase admin?

Answer 44

bolus dose over 1 min followed by infusion

Question 45

Alteplase SEs?

Answer 45

bleeding

Question 46

List the antiplatelet drugs

Answer 46

aspirin clopidogrel/ticlopidine/prasugrel/ticagrelor dipyridamole abciximab/eptifibatide

Question 47

Mehcanism of aspirin

Answer 47

inhibits platelet aggregation by irreversibly inhibiting COX | block PG and TXA2 production

Question 48

Where is aspirin absorbed?

Answer 48

upper GI tract

Question 49

Aspirin SEs

Answer 49

bleeding | GI irritation

Question 50

What are the ADP receptor blockers?

Answer 50

clopidogrel, ticlopidine, prasurgrel, ticagrelor

Question 51

Mechansim of clopidogrel et al?

Answer 51

inhibit ADP from binding P2Y12 | except for ticagrelor, irreversible antagonists

Question 52

What metabolises Clopidogrel/ticlopidine?

Answer 52

prodrugs, activated by CYP2C19

Question 53

What drug can potentially inhibit clopidogrel?

Answer 53

PPIs used to tx peptic ulcer (ie/ omeprazole)

Question 54

Clopidogrel SEs

Answer 54

bleeding dyspnea (ticagrelor) neutropenia (ticlopidine)

Question 55

What is the adenosine deaminase and phosphodiesterase inhibitor?

Answer 55

dipyridamole

Question 56

What is the end result of dipyridamole?

Answer 56

inhibits aggregation, may cause vasodilation, may also cause release of prostcyclin of PGD2, casues coronary vasodilation

Question 57

Dipyridamole SEs

Answer 57

headache, GI upset, dixxiness

Question 58

How do abciximab and eptifibatide work?

Answer 58

prevent platetlet aggregation by binding to CPIIb/IIIa to prevent fibrinogen binding/crosslinking platelets

Question 59

Is abciximab competitive?

Answer 59

no

Question 60

Is eptifibatide competitive?

Answer 60

yes

Question 61

Abciximab/eptifibatide admin?

Answer 61

IV

Question 62

Abciximab/eptifibatide SEs?

Answer 62

bleeding, thrombocytopenia hTN bradycardia use caution in pts w/renal dysfunction