[NSAID--COX-2-inhibitors, where is the difference? Focus on the modes of action]

Non-steroidal anti-inflammatory drugs (NSAID) induce their action by inhibiting prostaglandin synthesis via the cyclooxygenase enzymes (COX). COX has recently been shown to have at least two isoforms, termed COX-1 and COX-2. The life-threatening gastrointestinal side effects of NSAID are caused by their inhibition of COX-1, which results in increased gastrointestinal bleeding and decreased ability to induce platelet aggregation. Highly specific COX-2 inhibitors are now available. These have the same ability to relieve pain, but do not cause gastrointestinal bleeding or prolong bleeding time. However, many other side effects caused by NSAID are due to COX-2 inhibition and COX-2 inhibitors should still be used with caution when patients suffer from lung, heart, or kidney diseases.