Does clopidogrel inhibit CYP2C19?
Although clopidogrel is the most commonly prescribed P2Y12 inhibitor, it is associated with an increased risk of major adverse cardiovascular events in patients carrying loss-of-function CYP2C19 alleles. In contrast, CYP2C19 genotype does not impact clinical response to prasugrel or ticagrelor.
Does clopidogrel prevent platelet aggregation?
Clopidogrel, another thienopyridine, is a safe and promising alternative, that irreversibly inhibits ADP-induced platelet aggregation, and reduces formation of both arterial and venous thrombi.
What is the bioavailability of clopidogrel?
Clopidogrel
| Clinical data | |
|---|---|
| Bioavailability | >50% |
| Protein binding | 94–98% |
| Metabolism | Liver |
| Onset of action | 2 hours |
What effect does the CYP2C19 poor metabolizer phenotype have on clopidogrel?
Given these findings, in 2013, the FDA approved drug label for clopidogrel (Plavix) warning that patients who are CYP2C19 poor metabolizers may have diminished effectiveness of the drug, leading to higher cardiovascular event rates following acute coronary syndrome or percutaneous coronary intervention, as compared to …
How long Plavix inhibit platelets?
This action is irreversible. Consequently, platelets exposed to clopidogrel’s active metabolite are affected for the remainder of their lifespan (about 7 to 10 days). Platelet aggregation induced by agonists other than ADP is also inhibited by blocking the amplification of platelet activation by released ADP.
What should I monitor with clopidogrel?
Conclusion: The flow cytometric VASP-assay, the VerifyNow P2Y12 assay and, although to a lesser extent, 20 micromol L(-1) ADP-induced LTA correlate best with the maximal plasma level of the AMC, suggesting these may be the preferred platelet function tests for monitoring the responsiveness to clopidogrel.
How common is clopidogrel resistance?
Among people from western countries, nearly 30 percent are estimated to have clopidogrel resistance, with about 3 percent classified as poor metabolizers.
How long does clopidogrel stay in system?
Plavix is estimated to be cleared from your body in about 33 hours. A single, oral dose of Plavix (clopidogrel) 75 mg has a half-life of approximately 6 hours. It takes 5.5 x half-life of a medicine for a drug to leave the body, therefore most of the Plavix should be eliminated from your system in 5.5 x 6 = 33 hours.
What is the half-life of clopidogrel?
After a single, oral dose of 75 mg, clopidogrel has a half-life of approximately 6 hours. The elimination half-life of the inactive acid metabolite was 8 hours after single and repeated administration.
What is the duration of antiplatelet effect of clopidogrel?
At regular doses (75 mg daily), clopidogrel achieves a peak plasma level 2 h after oral ingestion and a plateau of inhibition of platelet aggregation (IPA) of 40–60% after 3–7 days.
How long does 75mg of Plavix stay in your system?
A single, oral dose of Plavix (clopidogrel) 75 mg has a half-life of approximately 6 hours. It takes 5.5 x half-life of a medicine for a drug to leave the body, therefore most of the Plavix should be eliminated from your system in 5.5 x 6 = 33 hours.
How do you measure the effectiveness of clopidogrel?
Because the mechanism of clopidogrel’s antiplatelet effect is blockade of the P2Y12 ADP receptor (Figure 1), clopidogrel’s effect on platelet function can be measured by stimulation of platelets with ADP and the use of 1 of a number of readouts (eg, phosphorylation of vasodilator-stimulated phosphoprotein measured by …
How do you monitor the effects of clopidogrel?
Conclusions: VASP phosphorylation assays are reliable for quantifying clopidogrel effects. Because the VASP assay directly measures the function of the clopidogrel target, the P2Y12 receptor, the assay is selective for clopidogrel effects rather than effects of other platelet inhibitors commonly in use.
What causes clopidogrel resistance?
Causes. Many genes are involved in converting clopidogrel to its active form and in determining the drug’s effects in the body. The CYP2C19 gene is particularly important for the activation of clopidogrel, and certain common variations (polymorphisms) in this gene have been associated with clopidogrel resistance.
Why do some patients not respond to clopidogrel?
The interpatient variability in clopidogrel response is multifactorial. It can be due to extrinsic or intrinsic mechanisms. Among extrinsic mechanisms are the possibility of clopidogrel underdosing in patients undergoing stenting or with acute coronary syndrome, and drug-drug interactions involving CYP3A4.