Clopidogrel / PPI interaction
In May 2009, the EU Committee for Medicinal products for Human Use (CHMP) concluded that concomitant use of any Proton Pump Inhibitor (PPI) with clopidogrel should be avoided unless considered essential.
This was based on pharmacokinetic, pharmacodynamic, and some clinical outcome data, which demonstrated that omeprazole competitively inhibits the
CYP2C19 isoenzyme (which metabolises clopidogrel to its active metabolite); reduces the ability of clopidogrel to inhibit platelet aggregation; and reduces the beneficial effect of
clopidogrel in patients.