Ibuprofen can cause illness

1. Ibuprofen can increase the risk of heart trouble and has been linked to heart attacks, strokes, and blood clots — all of which can be deadly.
2. Ibuprofen can damage the lining of your stomach, putting you at risk for stomach ulcers and heartburn.

 Source
 http://www.everydayhealth.com/drugs/ibuprofen