Antiplatelets

Question 1

Aspirin

Answer 1

MOA: Irreversible COX inhibitor on COX1 and COX2
Indications: Used for pain and to decrease risk of heart attacks and strokes at lower doses
Side effects: increased risk of bleeding
PK: lasts as long as the platelet (7 days)

Question 2

Ibuprofen

Answer 2

MOA: Reversible COX inhibitor or NSAID and blocks ASA binding site
Indications: pain
Side effects: increased risk of bleeding
DDI: aspirin
PK: lasts as long as the drug (3-5 t1/2s)

Question 3

Celecoxib

Answer 3

MOA: Selective COX inhibitor of COX2
Indications: pain and inflammation with lower risk of ulcers
Side effects: increased risk of thrombosis or clotting

Question 4

Clopidogrel (thienopyridines)

Answer 4

MOA: irreversible P2Y12 inhibitor and activated by CYP 2C19 as a prodrug
Onset: 2 hours
Dosing: q24h
DDI: omeprazole
Fun fact: genetic variability

Question 5

Prasugrel (thienopyridines)

Answer 5

MOA: irreversible P2Y12 inhibitor and activated by CYP 3A4, 2B6 as a prodrug
Dosing: q24h
Onset: 30 minutes

Question 6

Ticagrelor

Answer 6

MOA: Reversible P2Y12 inhibitor
Onset: 30 minutes
Dosing: BID

Question 7

Cangrelor

Answer 7

MOA: Reversible P2Y12 inhibitor
Onset: 2 minutes
Dosing: via IV but only lasts like 15-25 min

Question 8

Dipyrimadole

Answer 8

MOA: PDE inhibitor that increases cAMP which inhibits platelet activation and vasoconstriction
Indication: secondary stroke prevention

Question 9

Cilostazol

Answer 9

MOA: PDE inhibitor that increases cAMP which inhibits platelet activation and vasoconstriction
Indication: intermittent claudication

Question 10

Anagrelide

Answer 10

MOA: PDE inhibitor that increases cAMP which inhibits platelet activation and vasoconstriction
Indications: not antiplatelet because decreased it to too low so now used for thrombocytosis (leukemia)

Question 11

Vorapaxar

Answer 11

MOA: PAR-1 inmhibitor that is reversible by inhibiting thrombin receptors in platelets
PK: Long t 1/2
Indications: rarely used because not effective really

Question 12

SSRIs

Answer 12

MOA: inhibit 5HT uptake into platelet granules
Indications: depression, ect but shown to increase risk of GI bleeds to not used for anti-thrombotics now

Question 13

Abciximab

Answer 13

MOA: GP2b3a inhibitor that is a chimeric antibody fragment that persistently binds to receptor
PK: proteolytic elimination and half life is only 30 min but has antiplatelet effect up to 7 days

Question 14

Eptifibatide

Answer 14

MOA: GP2b3a inhibitor that is a cyclic 7-peptide inhibitor and reversibly binds to receptor
PK: renal elimination and half life is 2.5 hours with antiplatelet effect only 4-8 hours

Question 15

Tirofiban

Answer 15

MOA: GP2b3a inhibitor that is a nonpeptide and reversibly binds to receptor
PK: renal elimination and half life is 2 hours with antiplatelet effect only 4-8 hours