These papers may be helpful:

Clopidogrel, CYP2C19 and proton pump inhibitors: what we know and what it means.Hariharan S, Southworth MR, Madabushi R. J Clin Pharmacol. 2014 Aug;54(8):884-8.

Postgrad Med. 2014 May;126(3):239-45. doi: 10.3810/pgm.2014.05.2772.

Proton-pump inhibitors in patients requiring antiplatelet therapy: new FDA labeling.

Johnson DA1, Chilton R, Liker HR.

Expert Rev Clin Pharmacol. 2010 Jan;3(1):89-102. doi: 10.1586/ecp.09.58.

Interaction between clopidogrel and proton-pump  inhibitors.

Ly V1, Czosnowski L, McCluggage LK, Spinler S.

Thanks Beatrice for these valuable papers

Victoria is right. Do you know when the whole mess came out?. During the clinical marketing period of...guess what? Prasugrel.

Pantaprazole better then other ppi bcos will need one. 

Great Ankush! Our gut men really tell us to go through bleeding risk stratification before prescribing PPIs, but nobody cares. Obviously, this thread makes sense only in consideration of DAPT.

The attached article of metaanalysis of RCT may be useful. The result appears marginal.  At present the concomitant use of clopidogrel and omeprazole is designated as 'warning/precaution' not 'contraindication' based on USFDA.

What mainly counts is platelets reactivity. So one can measure the reactivity in patients on current PPI and clopidogrel and later, even in the same patients, only on clopidogrel. Stopping PPI for a few days is not very risky. There are in theory other possible ways of increasing risk of MI by PPI, for example by compromising group B vitamins (eg B12) availability and as a result influencing homocysteine metabolism. Homocysteine is not very harmful in general population but in CAD patients it can be detrimental. The other way of resolving the question is to measure clopidogrel active metabolit by suitable analytic technique in patient on clopidogrel and PPI and off PPI. Moreover clopidogrel dosage is usually high enough to minimize possible effects of PPI resulting from common metabolic pathway.