Treating minor aches and pains caused by the common cold, headaches, toothaches, back or muscle aches, menstrual cramps, or arthritis. It may be used to reduce fever. It may also be used for other conditions as determined by your doctor. Ibuprofen is an NSAID. Exactly how it works is not known. It may block certain substances in the body that are linked to inflammation. NSAIDs treat the symptoms of pain and inflammation. They do not treat the disease that causes those symptoms.