Nonsteroidal antiinflammatory drugs (NSAIDs) are a group of compounds with similar therapeutic and side effects. Their therapeutic effects depend on blockade of prostaglandin synthesis through enzyme cyclooxygenase (COX) inhibition. Two isoforms of the enzyme cyclooxygenase have been identified: COX-1 and COX-2. Selective COX-2 inhibitors i.e. meloxicam, nimesulid, etodolac or highly selective COX-2 inhibitors i.e. celecoxib, rofecoxib have antiinflammatory and analgesic properties with less or no gastrointestinal or other NSAIDs-typical adverse effects. Highly selective COX-2 inhibitors may also be active in colonic polyposis, colorectal cancer and Alzheimer's disease.