L28 - Anticoagulant therapy

Question 1

Name the three classes of antiplatelet drugs

Answer 1

Cyclooxygenase inhibitor
ADH receptor antagonist
Glycoprotein IIb, IIIa receptor inhibitors

Question 2

What is the mode of action of aspirin

Answer 2

Inhibits cyclooxygenase
Decrease TXA2
Decresae platelet aggregation

Question 3

What is the clinical usage of aspirin

Answer 3

Myocardial infaction and stroke

Use in combination with ADH receptor anatgonist in stenting and coronary angioplasty

Question 4

What are the side effects of aspirin

Answer 4

Risk of prolonged bleeding and increase incidence of gastric irritation and bleeding

Question 5

What are the two examples of ADH receptor antagonist

Answer 5

Clopiogrel

Prasugrel

Question 6

What is the mode of action of ADH receptor anatogonist

Answer 6

Inhibit ADH pathway

Decrease platelet aggregation

Question 7

What is the clinical usage of ADH receptor anatgonist

Answer 7

Use in patient who can’t tolerant aspirin

Use in combination with aspirin for stenting and coronary angioplasty

Question 8

What are the examples of glycoprotein IIb, IIIa receptor inhibitors

Answer 8

Abciximab

Eptifitabine, tirofiban

Question 9

What is abciximab?

Answer 9

It is a monoclonal antibodies binding IIb/ IIIa receptor

Question 10

What are eptifibatine and tirobatine

Answer 10

reversible inhibitors for IIb and IIIa receptor

Question 11

What are the mode of action of IIb/ IIIa receptor antagonist

Answer 11

IIb/ IIIa are finial commmon pathway for activation of platelets (binding to fibrinogen)
IIb/ IIIa inhibit that

Question 12

What is the clinical usage of glycoprotein IIb/ IIIa receptor antagonist

Answer 12

Stenting and coronary angioplasty

Question 13

What are APTT and PT used for in monitoring drug usuage

Answer 13

APTT: heparin
PT: warfin

Question 14

What are the pharmacological properties of heparin (short term? long term? cross placenta?)

Answer 14

Intermediate - short term use

Doesn’t cross placenta

Question 15

What are the usuage of heparin?

Answer 15

Stenting and coronary angioplasty

Myocardial infarction

Question 16

What are the side effects and contraindication of heparin

Answer 16

Bleeding
Haemophilia
Hypersensitivity reaction

Question 17

What is the pathogenesis of HIT

Answer 17

Antibody development
Target against heparin
Decrease in paltelet, thrombosis

Question 18

What is the treatment for HIT

Answer 18

Removal of heparin treatment
Protamine sulphate -> combined with heparin as a stable complex
Direct thrombin inhibitor

Question 19

What is the mode of action of heparin

Answer 19

It allow stronger binding of antithrombin to factor X and thrombin
Inhibit the coagulation pathway

Question 20

Give two other relatives of heparin

Answer 20

Exonaparin

Fondaparinux

Question 21

Give three examples of direct thrombin inhibitor

Answer 21

Oral - dabigatron

Parenteral - hirudin, lepirudin, argatroban

Question 22

What is the mode of action of thrombin inhibitor

Answer 22

Inhibition of thrombin -> decrease fibrin production and platelet activation -> no clot is produced

Question 23

Give an example of direct factor Xa inhibitor

Answer 23

Rivaroxaban, apixaban

Question 24

What is the mode of action of warfin

Answer 24

It is structually similar to vitamin K, acting as an antagonist

Question 25

How is warfin metabolised

Answer 25

Heavily protein bound an by liver cytochrome P450 enzmye

Question 26

What are the clinical uses of Warfin

Answer 26

Short term: prevent venous thrombosis and pulmonary embolism Long term: atrial fibrillation --> reduction of thrombosis prosthetic heart valve --> clot formation

Question 27

What are the adverse effects of warfin

Answer 27

Bleeding Cross placenta Interaction with significant number of drugs

Question 28

How to reverse warfin toxicity

Answer 28

Dtop using the drugs | Prescribe vitamin K1

Question 29

Name the four types of thrombolytic drugs and their pharmacological properties/ mode of action

Answer 29

Streptokinase - form comple with proactivator complex => conversion of plasminogen to plasmin => plasmin break down fibrin Anitreplase - streptokinase plasminogen complex Urokinase -enzymatic activity -> convert plasminogen to plasmin tPa -> direct activation of plasminogen -> plasminogen to plasmin -> plasmin breaks down fibrin

Question 30

What are the therapeutic use of thrombolytic drugs

Answer 30

Multiple pulmoanry emboli, central deep venous thrombosis, acute myocardial infarction

Question 31

What is the adverse effect of thrombolytic drugs | What can the side effect be treated with

Answer 31

Bleeding | Tranexamic acid or fresh plasma or coagulation factor

Question 32

What are the source of vitamin K

Answer 32

K1 - green vegetables | K2 - bacteria in the human gut

Question 33

Give two examples of fibrinolytic inhibitors

Answer 33

Aminocaproic acid | Tranexamic acid

Question 34

What is the mode of action of fibrinolytic inhibitors

Answer 34

competitor inhibitor of plasminogen activation