Hormone-like substances produced by nearly every tissue of the body that play a powerful role in inflammation. In the 1970’s, scientists discovered that nonsteroidal anti-inflammatory drugs (NSAIDs) reduce inflammation and manage pain by decreasing the body’s production of prostaglandins. Yet some prostaglandins protect the gastrointestinal tract (including the stomach and intestines) from injury. This means that NSAIDs may adversely affect the gastrointestinal tract, causing ulcers, at least in part because they decrease the production of these protective prostaglandins.
Certain substances called cyclooxygenase (COX) enzymes create prostaglandins in the body. There are at least two different forms of COX enzymes — COX-1 and COX-2. COX-1 is believed to aid in the production of protective prostaglandins in the gastrointestinal tract, while COX-2 plays a greater role in promoting inflammation throughout the body. A new type of NSAIDs called COX-2 inhibitors appears to inhibit prostaglandin production by COX-2 without affecting production by COX-1. Thus, COX-2 inhibitors can alleviate inflammation with fewer negative effects on the gastrointestinal tract. Celecoxib (brand name Celebrex) is the only COX-2 inhibitor currently available in the United States. Although previously available, COX-2 inhibitors valdecoxib (Bextra) and rofecoxib (Vioxx) were pulled from the market due to an increased risk of heart attack and stroke with long-term use.