Increased risk of bleeding w/ medicinal products associated w/ bleeding risk; oral anticoagulants; glycoprotein IIb/IIIa inhibitors; heparin; thrombolytics; NSAIDs including COX-2 inhibitors; SSRIs. Clopidogrel: Increased occult GI blood loss w/ naproxen. Increased levels of the active metabolite w/ strong CYP2C19 inducers (eg, rifampicin). Reduced levels of the active metabolite w/ strong or moderate CYP2C19 inhibitors (eg, omeprazole, esomeprazole, fluvoxamine, fluoxetine, moclobemide, voriconazole, fluconazole, ticlopidine, carbamazepine, efavirenz). Decreased exposure of the active metabolite w/ PPIs eg, omeprazole, esomeprazole. Reduced platelet inhibition in HIV patients treated w/ ritonavir- or cobicistat-boosted anti-retroviral therapy. Increased exposure of CYP2C8 substrates (eg, repaglinide, paclitaxel); rosuvastatin. Potentially delayed & reduced absorption w/ opioid agonists. ASA: Reduced effect on platelet aggregation w/ metamizole. Inhibited effect of uricosurics (eg, benzbromarone, probenecid, sulfinpyrazone). Inhibited renal clearance of MTX. Increased risk of renal failure w/ tenofovir disoproxil fumarate. Increased serum levels of total & free valproic acid. Risk of Reye's syndrome w/ varicella vaccine; patients should not be given salicylates for an interval of 6 wk after receiving varicella vaccine. Increased risk of metabolic acidosis w/ acetazolamide. Increased risk of GI ulceration, perforation & haemorrhage w/ nicorandil. Increased risk of GI injury w/ alcohol.