Drugs acting on Coagulation

Question 1

Which of the following helps with blood clot formation?

A. Low dose Aspirin
B. Warfarin
C. Vitamin K
D. Clopidogrel

Answer 1

C. Vitamin K

Question 2

List the anti-thrombotics

Answer 2

1. Low dose Aspirin
2. Clopidogrel

Question 3

List the anticoagulants

Answer 3

1. Heparin
2. Dalteparin
3. Enoxaparin
4. Warfarin
5. Rivaroxaban

Question 4

Which of the following is not an anticoagulant?

A. Heparin
B. Warfarin
C. Rivaroxaban
D. Clopidogrel

Answer 4

D. Clopidogrel
(anti-thrombotic)

Question 5

Which of the following drugs acts by inhibiting fibrinolysis?

A. Vitamin K
B. Protamine sulfate
C. Aminocaproic acid
D. Clopidogrel

Answer 5

C. Aminocaproic acid

Question 6

What drug is used as a specific antidote for anticoagulant rodenticide toxicity?

Answer 6

Vitamin K (hemostatic agent)

Question 7

How can Vitamin K be administered??

Answer 7

SQ and oral

anaphylaxis if given IV

Question 8

What is the DOC for treatment of hemorrhage secondary to heparin overdose?

A. Vitamin K
B. Protamine Sulfate
C. Tranexamic Acid (TXA)
D. Desmopressin

Answer 8

B. Protamine Sulfate

• binds to heparin and inactivates it

Question 9

What is the MOA of Protamine Sulfate?

Answer 9

• binds to heparin and inactivates it

Question 10

List the hemostatic agents

Answer 10

1. Vitamin K
2. Protamine sulfate
3. Aminocaproic acid
4. Tranexamic acid
5. Desmopressin

Question 11

List the thrombolytics

Answer 11

1. Streptokinase
2. Urokinase
3. Tissue plasminogen activator

Question 12

Vitamin K is necessary for synthesis of coagulation factors __________

Answer 12

II, VII, IX, X

2, 7, 9, 10

Question 13

When would use of protamine sulfate be contraindicated?

Answer 13

If pre-existing thrombosis

(excessive clotting will make it worse)

Question 14

What is the DOC for treatment of bleeding due to vonWillebrands disease?

Answer 14

Desmopressin

• Increases plasma factor VIII and plasminogen factor

Question 15

What is the MOA of Desmopressin?

Answer 15

• Increases plasma factor VIII and plasminogen factor
• Supports primary hemostasis and platelet function

Question 16

Main clinical indications for use of Desmopressin?

Answer 16

• DOC for tx of bleeding due to vonWillebrands dz
• DOC for tx of central diabetes insipidus
• Tx of bleeding due to aspirin toxicity

Question 17

_________ guidelines are available for use of antithrombotics and anticoagulants

Answer 17

CURATIVE

Question 18

What is the MOA of low dose aspirin?

Answer 18

Antithrombotic

• Reduces PLT aggregation by irreversibly inhibiting synthesis of Thrombozane A2 (TXA2)

Question 19

When is low dose aspirin used as antithrombotic agent?

Answer 19

1. Tx of thrombotic dz
2. Feline aortic thromboembolism
3. IMHA
4. Hypercoagulable states

Question 20

When is use of low dose aspirin contraindicated?

Answer 20

Contraindicated if pre-existing GI ulceration or active GI bleeding

Question 21

What drug would be best to treat feline aortic thromboembolism?

Answer 21

Clopidogrel (anti-thrombotic)

Question 22

What are the main clinical indications for use of Clopidogrel?

Answer 22

1. Tx of thrombotic dz
2. Feline aortic thromboembolism
3. IMHA
4. Hypercoagulable states

Question 23

What is the MOA of Clopidogrel?

Answer 23

• Reduces PLT aggregation by selectively inhibiting ADP on the PLT surface

Question 24

When is use of Clopidogrel contraindicated?

Answer 24

Contraindicated if pre-existing GI ulceration or active GI bleeding

Question 25

What is the MOA of unfractionated Heparin?

Answer 25

- Anticoagulant - Binds to Antithrombin III to inactivate factor XA and prevents conversion of prothrombin to thrombin

Question 26

Which of the following drugs are low molecular weight heparins?

Answer 26

1. Dalteparin 2. Enoxaparin

Question 27

What is the MOA of Dalteparin?

Answer 27

- Binds to Antithrombin III to inactivate factor XA (Has minimal effects on thrombin and clotting times unlike unfractionated heparin)

Question 28

What is the MOA of Enoxaparin?

Answer 28

- Binds to Antithrombin III to inactivate factor XA (Has minimal effects on thrombin and clotting times unlike unfractionated heparin)

Question 29

Which of the following has the most risk of causing prolonged aPTT coagulation time? A. Unfractionated heparin B. Enoxaparin C. Dalteparin D. Desmopressin

Answer 29

A. Unfractionated heparin (anticoagulant)

Question 30

What is the MOA of Warfarin?

Answer 30

- Inhibits Vitamin K epoxide reductase - Interferes with Vitamin K synthesis of coagulation factors II, VII, IX, X

Question 31

Warfarin toxicity is reversible with?

Answer 31

Vitamin K1 or frozen plasma transfusion

Question 32

What adverse effects can be seen with warfarin use?

Answer 32

- Prolonged clotting times (PT) - Life threatening hemorrhage

Question 33

Which 2 drugs have the most risk of causing prolonged PT/PTT clotting times?

Answer 33

- Unfractionated heparin (anticoagulant) - Warfarin (anticoagulant)

Question 34

Which of the following drugs is a direct Factor XA inhibitor?

Answer 34

Rivaroxaban

Question 35

What is the MOA of Rivaroxaban?

Answer 35

Direct factor XA inhibitor

Question 36

What is the MOA of streptokinase?

Answer 36

Activates plasminogen to breakdown existing clots (thrombolytic)

Question 37

What is the MOA of urokinase?

Answer 37

Activates plasminogen to breakdown existing clots (thrombolytic)

Question 38

What adverse effects can be seen with use of thrombolytics (Streptokinase, Urokinase, Tissue plasminogen activator)?

Answer 38

Life threatening hemorrhage

Question 39

What is the MOA of clopidogrel? A. Anti-PLT aggregation through TXA2 inhibition B. Anti-PLT aggregation through ADP inhibition C. Anti-coagulation through factor XA inhibition D. Antifibrinolysis

Answer 39

B. Anti-PLT aggregation through ADP inhibition

Question 40

Which of the following is a fibrin clot-specific thrombolytic? A. Streptokinase B. Urokinase C. Dalteparin D. Tissue plasminogen activator

Answer 40

D. Tissue plasminogen activator