CONTEXT It is unknown whether patients are at increased short-term risk for adverse events following clopidogrel cessation. OBJECTIVE To assess the rates of adverse events after stopping treatment with clopidogrel in a national sample of patients with acute coronary syndrome (ACS). DESIGN, SETTING, AND PATIENTS Retrospective cohort study of 3137 patients with ACS discharged from 127 Veteran...

BACKGROUND Clopidogrel is an inactive prodrug; it is converted to its active metabolite through the cytochrome P450 (CYP3A4) pathway, which also metabolizes calcium channel blockers (CCBs). Several studies have reported that CCBs reduce the ability of clopidogrel to inhibit platelet aggregability; one suggested that CCBs reduce the efficacy of clopidogrel. METHODS AND RESULTS We performed a p...

BACKGROUND There are limited prospective data on clopidogrel resistance and clinical outcome of patients with selective coronary drug-eluting stent (DES) implantation. OBJECTIVE To investigate whether clopidogrel resistance is associated with long-term thrombotic events in patients with selective coronary DES implantation. METHODS A total of 154 patients who underwent selective percutaneous...

Clopidogrel decreases the morbidity and mortality associated with several cardiovascular diseases. However, clopidogrel is a prodrug that needs to be metabolized to the active thiol metabolite by the cytochrome P450 (CYP) system. This activation is a source of significant interindividual variability in clopidogrel responsiveness. Drug interactions with and genetic variation in CYP3A4, CYP3A5, a...

Previous mechanistic studies have suggested a possible interaction between proton pump inhibitor (PPIs) and clopidogrel. However, the results of clinical trials about the effects of PPIs on safety and efficacy of clopidogrel are controversial. The study sought to estimate the impact of PPIs on antiplatelet effect of clopidogrel. The study performed a meta-analysis of comparative concomitant use...

Aspirin (acetylsalicylic acid) and clopidogrel are two major antithrombogenic agents that are widely used for the treatment and prevention of cerebro- and cardiovascular conditions such as stroke. Combined use produces enhanced therapeutic effect. Aspirin and clopidogrel both are esters, and hydrolysis leads to decreased or inactivated therapeutic activity. The aim of the study was to determine...

Clopidogrel has been recently approved for treatment of non-ST-elevation acute coronary syndromes based on the Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE) trial. However, the trial's findings are confounded by issues that lessen its clinical significance. Clopidogrel did not reduce mortality; its benefit was limited to preventing myocardial infarction, which was defined le...

BACKGROUND Interindividual variability of platelet inhibition after aspirin or clopidogrel administration has been described. Additionally, aspirin resistance and clopidogrel resistance occur in some individuals. Because the prodrug clopidogrel is activated by hepatic cytochrome P450 (CYP) 3A4, we hypothesized that interindividual variability in clopidogrel efficacy might be related to interind...

Clopidogrel reduces ischaemic complications in a wide range of patients with coronary artery disease. However, there is much inter-individual variation in clopidogrel-induced platelet inhibition, and a substantial proportion of patients will exhibit non-responsiveness to clopidogrel. Multiple studies have demonstrated an association between the presence of genetic polymorphisms associated with ...

Clopidogrel is a pro-drug that requires activation by the cytochrome P450 (CYP) enzyme system. Patients receiving clopidogrel are often treated with selective serotonin reuptake inhibitors (SSRIs) for co-existing depression. SSRIs that inhibit the CYP2C19 enzyme have the potential to reduce the effectiveness of clopidogrel. Using 5 US databases (1998 to 2013), we conducted a cohort study of adu...