Increased risk of serious CV thrombotic events, MI & stroke; serious GI adverse events including bleeding, ulceration & perforation of the stomach or intestines. Long-term administration may result to renal papillary necrosis & other renal injury; renal toxicity in patients whom renal prostaglandins have a compensatory role in the maintenance of renal perfusion; patients at risk of renal effects are those w/ impaired renal function, heart failure, liver dysfunction, those taking diuretics & ACE inhibitors. Advanced renal disease. Elderly.