Since eicosanoids are soluble mediators of the inflammatory response, their role critical in many types of immune reaction. One of the most widely used drugs in the world, aspirin, is a cyclooxygenase inhibitor that reduces prostaglandin synthesis. The anti-inflammatory effect of aspirin and other nonsteroidal an nflammatory drugs (NSAIDs) is due to blocking of the metabolism of arachidonic acid clooxygenase. Some animal studies suggest that high doses of other prostaglandin inhibitors, like indomethacin, may enhance some mononuclear cell dependent r sponses. There are limited reports that humans with deficient immune responses respond to indomethacin treatment whereas some normal individuals do not benefit from treatment with this drug and others show an increase in certain antibody re sponses [2]. The variation in response might be a function of which eicosanoid is involved in the altered immune responses. Burn injury leads to elevations of pros taglandin E and immune hyporesponsiveness. Administration of prostaglandin inhib- itors lowers the PGE levels and partially corrects the immune response. NSAID administration appears to prevent colon both humans and animals; in addition, prostaglandin synthesis is decreased by these drugs. It is un known how these compounds inhibit the growth of colon cancer [3]. While there be direct effects of these prostaglandin inhibitors on several aspects of colon carcinogenesis, including changes in cell metabolism, the cell cycle, and expression of tumor suppressor proteins, one cannot rule out alterations in immune response