DO PROTON-PUMP INHIBITORS RAISE THE RISK OF HEART ATTACKS? “Research by John P. Cooke, clinical professor and chair of the department of cardiovascular sciences at Houston Methodist Hospital, found that stomach acid-suppressing proton pump inhibitors (brand names Prilosec, Nexium, Prevacid) may cause blood vessels to constrict, reducing blood flow.” They lower nitric oxide levels. Solution: Arginine? I take nitric-oxide-boosting weightlifting supplements that are basically arginine. I wonder if that helps?