Last reviewed on RxList 4/8/2015. Motrin (ibuprofen) is a nonsteroidal anti-inflammatory drug (NSAID) indicated for relief of the signs and symptoms of rheumatoid arthritis and osteoarthritis, for relief of mild to moderate pain, and for treatment of primary dysmenorrhea. A generic formulation is available. Side effects of Motrin include stomach pain, constipation, diarrhea, bloating, gas, heartburn, nausea, vomiting, dizziness, headache, nervousness, skin itching or rash, blurred vision, or ringing in the ears.