Problems with proton pump inhibitors and Plavix?

▸ Ho MP, Maddox TM, Wang L, et al. Risk of adverse outcomes associated with concomitant use of clopidogrel and proton pump inhibitors following acute coronary syndrome. JAMA 2009;301:937–44.

▸ Jurlink DN, Gomes T, Ko DT, et al. A population based study of the drug interaction between PPIs and clopidogrel. CMAJ 2009;180:713–8.

Proton pump inhibitors (PPIs) are the mainstay of treatment of acid-related upper gastrointestinal symptoms, but recently concerns have been raised of more subtle adverse effects of PPIs such as association with pneumonia and hip facture. The latest of these is the possibility that these drugs interfere with the benefits of clopidogrel (Plavix). Clopidogrel is a prodrug converted to the active metabolite by the hepatic CYP2C19 pathway that is also used to metabolize PPIs. It is possible that PPIs could inhibit CYP2C19 and thereby reduce the activity of clopidogrel.

Two studies have evaluated this in databases of patients discharged on clopidogrel after acute coronary syndromes. Juulink et al evaluated 2791 Canadian patients taking Plavix over the age of 65 who had been discharged from hospital after a myocardial infarction (MI). They found that those taking …