Antiplatelet

Question 1

Aspirin MOA

Answer 1

arachidonic acid inhibitor vie irreversible inhibition of COX I and II, inhibits thromboxane synthesis in platelets at small doses and prostacycline synthesis at large dose

Question 2

Long term doses of aspirin

Answer 2

UA/STEMI, and STEMI post PCI

Question 3

Aspirin Clinical uses

Answer 3

CAD/ACS, prevention of VTE in post op ortho, prevent systemic emboli in Afib, Stroke/TIA, PAD, pain, inflammation

Question 4

Aspirin ADRs

Answer 4

Bleeding tinnitus

Question 5

Aspirin Contraindications

Answer 5

ESRD, inherited or acquired bleeding disorders, children can exasperate infection (Reye’s syndrome), H/O GI bleeds (81 mg only)

Question 6

Aspirin Pearls

Answer 6

All CAD/ACS pt, All diabetics, Irreversible, platelet function should return in 7-10 days after d/c, T1/2 of both the drug and platelets are critical

Question 7

Dipyridamole (Persantine) MOA

Answer 7

phosphodiesterase III inhibitor, results in increase cAMP which inhibits platelets aggregation

Question 8

Depyridamole (Persantine) clinical uses

Answer 8

adjunct for prevention of embolic disease in valve replacement and stroke patients, used for cardiac stress tests for its role as a vasoldilator, given IV

Question 9

Aspirin and dipyridamole (Aggrenox)

Answer 9

primarily used for 1 and 2 stroke prevention, very well tolerated

Question 10

Cilostazol (Pletal) MOA

Answer 10

phosphodiesterase-III platelet inhibitor, reversible

Question 11

Cilostazol (Pletal) Clinical uses

Answer 11

PAD/intermittent claudication, usually a last resort

Question 12

Cilostazol (Pletal)

Answer 12

lots of drug interactions, contraindicated in heart failure, normal platelet function returns in 4 days after D/C

Question 13

Thienopyridines

Answer 13

Clopidogrel (Plavix), Prasugrel (Effient), Ticlodipine (Ticlid)

Question 14

Thienopyridines MOA

Answer 14

inhibit the binding of ADP to receptors by irreversibly modifying the receptor and prevent platelet aggregation

Question 15

Class dominates the oral antiplatelet market

Answer 15

thienopyridine

Question 16

Clopidogrel (Plavix)

Answer 16

a prodrug, irreversible, normal platelet function returns 7-10 days after d/c

Question 17

Clopidogrel (Plavix) clinical uses

Answer 17

NSTEMI, PCI w/stent, stroke, also continue aspirin to prevent restenosis

Question 18

Clopidogrel (Plevix) drug interactions

Answer 18

tranformation to active metabolite (CYP2C19), high degree of interpatient variability in CYP enzymes, genetic testing available

Question 19

Prasugel (Effient)

Answer 19

a prodrug, irreversible, produces more potent and consistent platelet inhibition compared to clopidogrel, avoids CYP2C19 interactions, shown to reduce risk of recurrent MI in ACS pts, platelet function return 5-9 days

Question 20

Prasugel (Effient) cautions

Answer 20

Caution in patients >75 yo and low body weight, must adjust, contraindicated in patients with active bleeding or history of stroke/TIA, increases risk of major bleeding

Question 21

Ticlopidine (Ticlid)

Answer 21

a prodrug, irreversible, very little dose, boxed warning surroundings use and subsequent development of hematologic toxicities

Question 22

Ticagrelor (Brilinta) MOA

Answer 22

similar to thienopyridines, but it is officially a cyclopentyltriazolopyrimidine, completely inhibits ADP through reversible receptor binding

Question 23

Ticagrelor (Brilinta)

Answer 23

BID, being to be given with aspirin 81 mg, not recommended with >100 mg aspirin cause bleeding, contraindicated in severe disease, reversible, faster? normal platelet function returns 3-5 days

Question 24

Ticagrelor (Brilinta) ADRs and DI

Answer 24

bleeding, dyspnea, ventricular pauses, bradyarrhythmias, N/D, hypotension, NSAIDs and warfarin increases bleeding, avoid with CYP2C19

Question 25

Anagrelide (Agrylin) MOA

Answer 25

phosphodiesterdase-3 inhibitor, inhibits cyclic nucleotide phosphodiesterase and the release of arachidonic acid

Question 26

Anagrelide (Agrylin) clinical uses

Answer 26

thrombocythemia, usually associated with myeloproliferative disorders

Question 27

Glycoprotein IIb/IIIa inhibitors

Answer 27

Eptifibatide (Intreglin), abciximab (reopro), Tirofiban (Aggrastat)

Question 28

Glycoprotein IIB/IIIa inhibitors MOA

Answer 28

blocks the platelet glycoprotein IIb/IIa which is the binding site for fibrinogen and von Willebrand factor, an antagonist at this receptor reversibly blocks platelet aggregation and prevents clotting

Question 29

Eptifibatide (Integrilin) clinical uses

Answer 29

acute coronary syndrome (STEMI, NSTEMI), percutaneous coronary intervention PCI

Question 30

Eptifibatide (Integrilin) contraindication

Answer 30

active abnormal bleeding within previous 30 days, history of stroke, severe HTN, major surgery within previous 6 weeks

Question 31

Eptifibatide (Integrilin) ADRs

Answer 31

bleeding, relative to anticoagulants, bleedings is much less of a concern with primary concern of bleeding at the point of catheter entry

Question 32

Eptifibatide (Integrilin) Pearls

Answer 32

hemostasis generally restored 4 hours after infusion is stopped because it is a reversible inhibitor, very $$$

Question 33

Abciximab (Reopro) Clinical uses

Answer 33

PCI, unstable angina/NSTEMI, STEMI, concurrent heparin and aspirin recommended for prevention of ischemic complications

Question 34

Abciximab (Reopro)

Answer 34

IV only, short term, apt to develop immune response, contraindicated with bleeding, need to monitor signs and symptoms of bleeding

Question 35

Abciximab (Reopro) ADRs

Answer 35

Bradycardia, hypotension, CP, Nausea, immunogenicity

Question 36

Tirofiban (Aggrastat)

Answer 36

Stabile ischemic heart disease undergoing elective PCI, unstabile angina/ NSTEMI, STEMI; IV only, short term use only via continuous infusion, quick onset 10 min, no major difference with this drug, very limited use