GASTROENTEROLOGY ARTICLE OF THE WEEK
March 25, 2010
Laine L, Hennekens C. Proton pump inhibitor and clopidogrel interaction: Fact or fiction? Am J Gastroenterol 2010;105;34-41.
1. Clopidogrel
a. Exerts its anti-platelet action only while there is detectable serum levels of clopidogrel
b. Heterozygotes with decreased function of CYP2C19 function have an increased relative risk of cardiovascular events when treated with clopidogrel compared to those with normal CYP2C19 function
c. Binds irreversible to platelet receptor causing long-lasting decrease in platelet aggregation.
d. Once discontinued, platelet function returns to normal in 2-3 days
e. Is metabolized via CYP2C19 into inactive metabolites
True or False
2. Randomized, prospective studies evaluating cardiovascular events in patients taking PPI + clopidogrel compared to clopidogrel alone have not been conducted.
3. Clopidogrel use may result in enhanced acid suppression by PPI’s
4. Lansoprazole and omeprazole are the most potent inhibitors of CYP2C19, pantoprazole and rabeprazole are the least potent.
5. Theoretically, separating the PPI administration time from the clopidogrel administration time by 8 to 10 hours may decrease the drug interaction
6. Patients at high risk of bleeding should receive dual anti-platelet therapy at least 2 weeks after bare metal stent and 3 to 6 months after drug-eluting stent
7. H2RA therapy reduces the risk of bleeding in patients taking aspirin + clopidogrel
8. Clopidogrel increases risk of gi bleeding by causing gastric ulcerations.
9. Patients with decreased function of the CYP2C19 have a greater benefit from PPI’s compared to those with full function of the CYP enzyme
10. In clinical trials, risk of cardiovascular events are less in the pantoprazole-clopidogrel combination compared to omeprazole-clopidogrel combination