Ibuprofen may cause ulcers, bleeding, or holes in the stomach or intestine.
I have no stomach problems unless I drink too much Starbucks coffee over a 3-day period.
I once cracked a rib and my doctor put me on 800 mg ibuprofen twice a day. _All_ pain went away as my swim times dropped steadily - so much so that it was upsetting the swim team's male hierarchy. Each new day I was recovered and invigorated, much to the irritation of my teammates. This went on for a month until the prescription expired. My swim times rose over the next 3 days as swimming became harder and the usual day-to-day pains returned.
Some people say that NSAIDs will prevent you from improving your ability in athletic events but that was not true for me and ibuprofen.
Around 3 years on that regimen so far.