Pharm 23: Clots and bleeds Flashcards
How does aspirin thin the blood
Inhibits the synthesis of prostaglandins, thereby inhibiting the platelet granule release reaction and interfering with normal platelet aggregation.
Aspirin inhibits (enzymes)
COX 1/2 non selective
In platelets, an increase in the concentration of intracellular ____ leads to a decrease in platelet _____
In platelets, an increase in the concentration of intracellular cAMP leads to a decrease in platelet aggregability
Inhibitors of platelet phosphodiesterase decrease platelet aggregability by inhibiting __________
Inhibitors of platelet phosphodiesterase decrease platelet aggregability by inhibiting cAMP degradation
Dipyridamole MOA
platelet phosphodiasterase inhibitor
decreased platelet aggregation
Dipyridamole is administered with _________
Why?
Warfarin/aspirin
kinda weak
Dipyridamole side effect
Vasodilation leading to angina
Drugs that inhibit ADP-dependent platelet activation
clopidogrel
ticlopidine
prasugrel
aka thienopyridines
Ticlopidine indications
1) Secondary prevention of strokes when aspirin allergy
2)Post stent thrombosis prophylaxis (with aspirin)
Clopidogrel metabolism
Prodrug via P450
Clopidogrel indications
Secondary stroke prevention post MI
Clopidogrel dosing considerations
Loading dose to achieve effect then maintanance
Prasugrel use
Acute coronary syndromes during PCI
Cath lab drug
Prasugrel major AE cosideration
Dont give to stroke bc of head bleed risk
Ticagrelor MOA
competitive P2Y12 ADP receptor antagonist
Tricagelor use
Acute coronary syndromes
Tricagelor route
Oral with no hepatic activation needed
Eptifibatide MOA
GPIIb–IIIa receptor antagonist
Platelet inhibition
Abciximab MOA
Chimeric mouse–human monoclonal antibody directed against the human GPIIb–IIIa receptor.
Tirofiban MOA
nonpeptide tyrosine analogue that reversibly antagonizes fibrinogen binding to the platelet GPIIb–IIIa receptor.
Eptifibatide, tirofiban and abxcimab how to reveres
Abxicimab: give more platelets
Others: Wait
Vorapaxar MOA
protease-activated receptor 1 (PAR-1) antagonist one of two major thrombin receptors