Nonsteroidal anti-inflammatory drugs (including fenoprofen) may rarely increase the risk of a heart attack or stroke. This effect can happen at any time while taking this drug but is more likely if you take it for a long time. The risk may be greater in older adults or if you have heart disease or increased risk for heart disease (for example, due to smoking, family history of heart disease, or conditions such as high blood pressure or diabetes). Do not take this drug right before or after heart bypass surgery (CABG).
Also, this drug may rarely cause serious (rarely fatal) bleeding from the stomach or intestines. This effect can occur without warning symptoms at any time while taking this drug. Older adults may be at higher risk for this effect.
Stop taking fenoprofen and get medical help right away if you notice any of these rare but serious side effects: stomach/abdominal pain that doesn't go away, black/tarry stools, vomit that looks like coffee grounds, chest/jaw/left arm pain, shortness of breath, unusual sweating, confusion, weakness on one side of the body, trouble speaking, sudden vision changes.
Talk to your doctor or pharmacist about the benefits and risks of taking this drug.