Major side effects can occur from the long-term use of non-steroidal anti-inflammatory drugs (NSAIDs). NSAIDs include ibuprofen drugs like Motrin and Advil or naproxen sodium drugs like Aleve. The risk is greatest when the long-term use is at high doses. Some side effects include stomach upset and ringing in the ears. Liver and kidney damage are possible as well as cardiovascular problems when NSAIDs are used at high doses over a long time to treat symptoms of mixed connective tissue disease (MCTD).