Các thuốc chống viêm không steroid (NSAIDs) có hoạt động chống viêm, giảm đau và hạ sốt. Tất cả các loại thuốc này có một số tác dụng phụ, nhưng ảnh hưởng bất lợi liên quan với thuốc NSAID thường xuyên nhất là đường tiêu hóa (GI) độc tính, một nguồn của cả hai bệnh tật và tử von | Advances in Therapeutics and Diagnostics Anti-inflammatory Medications Selective COX-2 Inhibitors Joseph M. Lane MD The nonsteroidal anti-inflammatory drugs NSAIDs generally possess anti-inflammatory analgesic and antipyretic activity. All of these medications have some adverse effects but the most frequently associated adverse effect with NSAIDs is gastrointestinal GI toxicity a source of both morbidity and mortality especially with prolonged usage in the elderly. Risk factors for the development of NSAID-induced gastric problems include individuals aged 60 years history of GI ulcer or bleeding concomitant use of corticosteroids or anticoagulants higher NSAID doses and serious systemic illnesses. The incidence of GI toxicity is 20 to 40 per 1 000 patient-years of Renal platelet and central nervous system toxicity also have been observed. Although no currently available NSAID lacks GI toxicity specific cyclooxygenase-2 COX-2 inhibition appears to be an improvement over conventional NSAIDs. The selective COX-2 inhibitor celecoxib was approved for use in the United States by the FDA in 1998 to treat osteoarthritis and rheumatoid arthritis. Rofecoxib was approved in 1999 for osteoarthritis acute pain and primary dysmenorrhea. Currently additional agents such as a parenteral form parecoxib and its active metabolite valdecoxib are under development. Structure and Mechanism of Action The anti-inflammatory effect of NSAIDs is due mainly to the inhibition of the COX enzymes which are required for the synthesis of prostaglandins and thromboxanes. The recycled oxygenases are biofunctional hemoproteins that catalyze the oxygenation of arachidonic acid to prostaglandin a common precursor for the synthesis of the family of prostaglandins prostacy-cline and thromboxanes. Two COX isoforms exist that catalyze the same reaction but are different in terms of regulation and expression Fig. 1 . COX-1 which is expressed constitutively in most tissues is thought to protect .
