C3.1 Anticoagulants

Question 1

NAME

1. direct acting anticoagulants
2. Indirect anticoagulants

Answer 1

Heparins: Heparin, LMW heparins: Enoxaparin, Fraxiparine, Dalteparin sodium
Factor Xa inhibitors: Rivaroxaban, Apixaban
Thrombin inhibitors: Lepirudin, Desirudin, Bivalirudin

2. Coumarins: Warfarin

Question 2

Name/ describe Heparin antagonist

Answer 2

Protamine sulphate: blocks protamine-hepatmine complex
Mechanism of action/Effect: Protamine is a strongly basic substance that combines with the strongly acidic heparin to form a stable (salt) complex.
The protamine-heparin complex has no anticoagulant activity

Question 3

Describe Warfarin mechanism of action

Answer 3

Inhibiting the synthesis of vitamin K-dependent clotting factors, which include Factors II, VII, IX, and X, and the anticoagulant proteins C and S

Question 4

DESCRIBE indirect acting anticoagulants

Answer 4

Vitamin K antagonists
Indirect-acting anticoagulants have no influence on coagulation factors directly in the blood
They supress the biosynthesis of coagulation proteins (Factor VII and prothrombin) in the liver as a result of antagonism with vitamin K.
- a decrease in blood coagulation
- an increase in fibrinolysis
- a decrease in lipids concentration in blood

Question 5

Define antiaggregant

- give examples

Answer 5

Drugs that decrease platelet aggregation

• COX-inhibitors: acetylsalicylic acid (aspirin)
• Inhibitors of phosphodiesterase -Dipyridamole
  Inhibitors of ADP-mediated aggregation: Ticlopidine, Clopidogrel

Question 6

Describe Acetylsalicllic acid

Answer 6

Blocks synthesis of thromboxane A2 by inhibting COX 2

Question 7

Describe Dipiridamol

Answer 7

Increases cAMP concentrations in the platelets that supresses clotting associated with TXA2

Question 8

Describe Clopidogrel & Ticlopidine

Answer 8

Block ADP-receptors in the platelet membrane