nonsteroidal antiinflammatory drug (NSAID) /-stir″oidəl/ , any of a group of drugs having antipyretic, analgesic, and antiinflammatory effects. They counteract or reduce inflammation by inhibiting cyclooxygenase, the enzyme responsible for prostaglandin synthesis. NSAIDs may be indicated in the treatment of mild-to-moderate pain, rheumatoid arthritis, osteoarthritis, ankylosing spondylosis, gouty arthritis, fever, nonrheumatic inflammation, and dysmenorrhea. Classic examples include aspirin, ibuprofen, and ketoprofen. Newer drugs such as celecoxib, refecoxib, and valdecoxib selectively block only the inductible form of cyclooxygenase (COX-2), the form of the enzyme that appears in cells at sites of inflammation, and tend to have fewer side effects.
