Plavix (clopidogrel): Reduced effectiveness in patients who are poor metabolizers of the drug
Audience: Cardiology healthcare professionals, patients
FDA notified healthcare professionals and patients that a Boxed Warning has been added to the prescribing information for Plavix, an anti-blood clotting medication. The Boxed Warning in the drug label will include information to:
- Warn about reduced effectiveness in patients who are poor metabolizers of Plavix. Poor metabolizers do not effectively convert Plavix to its active form in the body.
- Inform healthcare professionals that tests are available to identify genetic differences in CYP2C19 function.
- Advise healthcare professionals to consider use of other anti-platelet medications or alternative dosing strategies for Plavix in patients identified as poor metabolizers.
Plavix is given to reduce the risk of heart attack, unstable angina, stroke, and cardiovascular death in patients with cardiovascular disease. Plavix works by decreasing the activity of blood cells called platelets, making platelets less likely to form blood clots. A data summary and additional information for healthcare professionals and patients are provided in the linked Drug Safety Communication.
[03/12/2010 - Drug Safety Communication: Reduced effectiveness of Plavix (clopidogrel) - FDA]
[03/12/2010 - Information on Clopidogrel Bisulfate (marketed as Plavix) - FDA]