ANITPLATELETS Flashcards
Give the classes of antiplatelet drugs
1) COX-1 Inhibitors - Aspirin
2) ADP Receptor inhibitors - Ticlopidine and Clopidogrel
3) GPIIb/IIIa Receptor inhibitors - Abciximab , Eptifibatide and Tirofiban
4) Phosphodiesterase Inhibitors - Dipyridamole and Cilostazol
Give the following about Asprin
1) MOA
2) Dosing
Irreversible inhibition by acetylation of COX-1 thus no production of Thromboxane A2 which is a platelet aggregator and vasoconstrictor
75mg once daily
Give the following on Ticlopidine
1) MOA
2) Metabolism
3) Dosing
4) Most common adverse effect
5) Most serious adverse effect
6) why it was replaced with Clopidogrel
Permanent inhibition of ADP Receptor P2Y12 by formation of a disulfide bridge on the thiol of the drug and cysteine residue on the receptor
It is a prodrug and metabolized by active metabolite to its thiol metabolite.
250mg twice daily
Most common A/E is Nausea, Vomiting and diarrhea.
Most serious - Neutropenia
Replaced with Clopidogrel due to TTP and Blood dyscariasis
Clopidogrel is a prodrug that may cause resistance due to the action of which main enzyme responsible for its active metabolite
Resistance due to genetic polymorphism in CYP2C19
Clopidogrel is used together with asprin in what cases
after an angioplasty and coronary stenting
Give one difference between Abciximab and Eptifibatide + Tirofiban
Abciximab blocks both the GPIIb/IIa receptor and vitronectin while Eptifibatide and Tirofiban only lock the GPIIb/IIIa receptor
Both Dipyridamole and Cilostazol are phosphodiesterase inhibitors that increase levels of
cGMP.
The Phosphodiesterase inhibitors are vasodilators or vasoconstrictors
vasodilators - headache , hypotension
Give the A/E of the Phosphodiesterase inhibitors
GIT problems
Headache
Hypotension
Hypersensitivity reaction
Thrombocytopenia
Hot flashes , tachycardia
