Prescription NSAIDs are an important treatment for the symptoms of many debilitating conditions, including osteoarthritis, rheumatoid arthritis, gout and other rheumatological and painful conditions. OTC NSAIDs are used to temporarily reduce fever and to treat minor aches and pains such as headaches, toothaches, backaches, muscular aches, tendonitis, strains, sprains and menstrual cramps. Common OTC NSAIDs include ibuprofen (Motrin, Advil) and naproxen (Aleve). In addition, some combination medicines that relieve various symptoms, such as multi-symptom cold products, contain NSAIDs.
NSAIDs have anti-inflammatory (reduce inflammation), analgesic (relieve pain) and antipyretic (lower temperature) effects. Although different NSAIDs have different structures, they all work by blocking cyclooxygenase (COX) enzymes. There are two main types of COX enzymes: COX-1 and COX-2. Both types produce prostaglandins; however, the main function of COX-1 enzymes is to produce baseline levels of prostaglandins that activate platelets and protect the lining of the gastrointestinal tract, whereas COX-2 enzymes are responsible for releasing prostaglandins after infection or injury. Prostaglandins have a number of different effects, one of which is to regulate inflammation. Most NSAIDs inhibit both enzymes, although a few are available that mainly inhibit COX-2. The pain-relieving and anti-inflammatory effects of NSAIDs are mainly due to inhibition of COX-2, and their unwanted side effects are largely due to inhibition of COX-1.