Antiplatelets

Question 1

Uses of antiplatelets

Answer 1

platelet rich arterial thrombi

Question 2

Aspirin MoA

Answer 2

COX-1 inhibitor- irreversible
prevents formation of thromboxane A2 (platelet aggregation)
Higher doses inhibit PGI2

Question 3

Aspirin uses

Answer 3

Secondary prevention of stroke/ A fib/ TIA

NSTEMI/STEMI - 300mg loading dose

Question 4

Aspirin warnings

Answer 4

Reyes syndrome (hepatic failure <16 yrs)
Hypersensitivity (asthma)
3rd trimester of pregnancy- prematurely closes ductus arteriosus

Question 5

ADP receptor antagonist examples

Answer 5

Clopidogerl, prasugrel, ticagrelor

Question 6

MoA ADP receptor antagonist

Reversible and irreversible actions

Answer 6

Inhibit binding of ADP to P2Y12
Inhibits activation of GP11b/IIa
Clopidogrel and prasugrel- irreversible inhibitor
Ticagrelor has different binding site and is reversible

Question 7

ADP receptor antagonist uses

Answer 7

Aspirin contraindicated

Question 8

ADP receptor antagonist warnings

Answer 8

Renal and hepatic impairement

Prodrugs require hepatic activation

Question 9

ADP receptor DDI CYP

Answer 9

Prodrugs, requires hepatic activation via CYPs

Omeprazole (CYP inhibitor) reduces clopidogrel efficacy

Question 10

Phosphodiesterase inhibitor example

Answer 10

Dipyridamole

Question 11

Dipyridamole MoA

Answer 11

blocks reuptake and metabolism of adenosine
»prevents CAMP degradation
increase cAMP inhibits aggregation
inhibits expression of GPIIb/a

Question 12

Dipyridamole uses

Answer 12

Prophylaxis of thromboembolism following valve replacement

secondary prevention

Question 13

Glycoprotein IIb/IIIa inhibitors example

Answer 13

Abciximab- monoclonal antibody

Question 14

Glycoprotein IIb/a inhibitor MoA

Answer 14

blocks fibrinogen binding to vWF

blocks GPIIb/a receptors

Question 15

Streptokinase and alteplase MoA

Answer 15

Increase conversion of plasminogen to plasmin for fibrinolysis

Question 16

Dipyridamole ADR

Answer 16

Impending doom- breif ventricular asytole