P2Y12 Inhibitor Dosing Flashcards
clopidogrel: reversible or irreversible?
irreversible
prasugrel: reversible or irreversible?
irreversible
ticagrelor: reversible or irreversible?
reversible
clopidogrel: prodrug?
yes
prasugrel: prodrug?
yes
ticagrelor: prodrug?
no
clopidogrel binding site?
ADP binding
prasugrel binding site?
ADP binding
ticagrelor binding site?
allosteric
clopidogrel onset of action?
2-6 hours
prasugrel onset of action?
30 minutes
ticagrelor onset of action?
30 minutes
clopidogrel loading dose?
600mg
prasugrel loading dose?
60mg
ticagrelor loading dose?
180mg
clopidogrel metabolism?
converted by a 2 step process involving 2C19, patients can vary between being a fast or slow metabolizer so someone’s response to clopidogrel can vary
prasugrel metabolism?
single step via multiple pathways
ticagrelor metabolism?
3A4 primarily
clopidogrel percentage of platelet inhibition?
3-40%
prasugrel percentage of platelet inhibition?
60-70%
ticagrelor percentage of platelet inihbition?
60-70%
clopidogrel maintenance dose?
75mg daily
prasugrel maintenance dose?
10mg daily (remember: only for PCI!!!) 5mg if pt is <60kg or >75 years old
ticagrelor maintenance dose?
90mg BID for 12 months
60mg BID after 12 months
how soon to discontinue clopidogrel before surgery?
5 days
how soon to discontinue prasugrel before surgery?
7 days
how soon to discontinue ticagrelor before surgery?
5 days
interactions with clopidogrel
PPIs can decrease efficacy due to CYP2C19
high on treatment platelet reactivity occurs with what P2Y12 inhibitor?
may occur in about 30% of patients on clopidogrel, it means that the platelets are still very active and clopidogrel isn’t inhibiting them (this hasn’t been shown to change clinical outcomes)
contraindication of prasugrel
history of stroke or TIA.
if patient <60kg,
if patient is older than 75
contraindication of ticagrelor
history of cerebral bleed and severe liver disease
interactions with ticragelor
concomitant strong CYP3A4 inhibitors/inducers,
do not use with more than 100mg of aspirin (dose related dyspnea and bradyarrhythmias)
cangrelor (Kengreal) MOA
reduces ADP induced platelet activation and aggregation by inhibiting the P2Y12 receptor
cangrelor onset of action
within 2 minutes of bolus administration, normal platelet activity resumes within 60-90 minutes of discontinuation
cangrelor indications
PCI to reduce the risk of MI, repeat coronary revascularization, and stent thrombosis
how long to use a P2Y12 inhibitor for ACS?
preferably 1 year
how long to use a P2Y12 inhibitor for a bare metal stent?
minimum 1 month (this is because it is a foreign body that platelets will stick to and could cause another clot. Bare metal stents take less time to endotheliazie than drug eluting stents)
how long to use a P2Y12 inhibitor for a drug eluting stent?
minimum 3 months
