Drugs affecting blood

Question 1

Drugs affecting WBCs

Answer 1

Increase WBC numbers and function

*recombinant granulocyte colony-stimulating factors

Drugs: Neupogen, Neulasta

Question 2

Drugs affecting RBCs

Answer 2

-Erythropoietin and varients

Drugs: Molidustat, Pentoxifylline

Question 3

Drugs affecting platelets

Answer 3

-Aspirin
-clopidogrel

Question 4

Drugs affecting clot formation

Answer 4

-Streptokinase, tPA

Question 5

Drugs affecting coagulation

Answer 5

-Heparin
-Calcium chelators
-Vit K antagonists (warfarin, dicoumarol)

Question 6

Immune “stimulants”

Answer 6

-exogenous Granulocyte-Colony Stimulating Factor (G-CSF) = protein that stimulates precursors to WBCs (specifically neutrophils)

-used to increase circulating neutrophils, and activate neutrophil function (phagocytosis)

Question 7

Filgrastim, pegfilgrastim (Neupogen, Neulasta)

Answer 7

Recombinant form of human G-CSF
-occasionaly used in canine oncology patients because G-CSF structure similar in both humans and dogs

Question 8

Erythropoietin (EPO)

Answer 8

-produced by kidney peitubular interstitial cells; increases RBCs

-only injectables

-used for:
1. Anemia from chronic kidney disease
2. Myelodysplasia
3. Performance enhancing drug

Question 9

Thrombosis

Answer 9

formation of a solid blood clot in a blood vessel

Question 10

Thromoboembolism

Answer 10

clot that is free to move in circulation

Question 11

Antithrombotic drugs

Answer 11

Prevent thrombosis BUT not enough to cause hemorrhage
-Arterial or venous thrombosis (infection, inflammation, cancer)
-Pulmonary thrombosis and embolism (due to IMHA)
-DIC

Question 12

Thrombus formation

Answer 12

1. vessels contract
2. Platelets adhere
3. Platelets aggregate to form platelet plug
4. Activation of coagulation pathway results in activation of enzyme thrombin
5. Thrombin catalyzes fibrinogen into fibrin
   Stabilizing the plug (thrombus)

Question 13

Coagulation cascade key points

Answer 13

1. Ca is extremely important so if you use Ca chelators then will delay coagulation cascade
2. Vit K dependency- so inhibit Vit K= anticoagulation

Question 14

Calcium Chelators

Answer 14

-Sodium citrate, sodium oxalate, EDTA, sodium fluoride

-good for blood collection and blood storage

-NOT used as anticoagulant drugs

Question 15

Where is Heparin produced?

Answer 15

-produced in mast cells
-glycosaminoglycan (GAG), negatively charged polyanion
-used in multiple antithrombotic drugs (IV or SC)

Question 16

Significant anticoagulant activity of heparin

Answer 16

1. inactivated factors IX, X, XI, XII and antithrombin
2. Prevents conversion of prothrombin to thrombin

3, Prevents conversion of fibrinogen to fibrin

4. Prevents stabilization of fibrin clots

Question 17

What does heparin act through?

Answer 17

Acts through antithrombin III and heparin cofactor II

Question 18

Coumarin derivatives

Answer 18

-dicoumarol and warfarin

-Anticoagulant= inactivate vit K, interfering with vit K dependent coagulation factors

-long term oral administration may be needed

Question 19

Prothrombin time

Answer 19

used to determine when fibrin strands begin to form
-used to determine dose of coumarin derivatives

Question 20

Thrombolytics

Answer 20

Enhance clot breakdown by stimulating conversion of plasminogen to plasmin

-includes Streptokinase or tissue type plasminogen activator (tPA)

Question 21

Drugs preventing platelet activation

Answer 21

*decreased platelet aggregation and plug formation

-includes aspirin and clopidogrel

Question 22

Aspirin mechanism

Answer 22

Blocks thromboxane receptors

Question 23

Clopidogrel mechanism

Answer 23

ADP-receptor antagonists
-minimizes platelet aggregation