As some controversy is attached to the use of metamizol because of the risk of agranulocytosis (metamizol was withdrawn from the Scandinavian market in 1999), some hospitals do not use the drug. The use of NSAIDs is likewise problematic. They can cause, for example, gastric ulcers in predisposed patients. In the setting of the stress accompanying surgery, however, even previously unremarkable patients can quickly develop stress ulcers. Another problem with NSAIDs is that they affect blood clotting to various extents by inhibiting platelet aggregation. This aspect is particularly crucial in the early treatment of postoperative pain when intact blood clotting is essential. An ideal analgesic for postoperative pain would not induce respiratory depression nor affect blood clotting nor cause gastric ulcers. Because inhibiting the enzyme cyclooxygenase-1 (COX-1) increases the effects on the gastric mucosa and on platelet aggregation, an analgesic should selectively inhibit only the enzyme cyclooxygenase-2 (COX-2), which mediates inflammatory processes. This is the rationale behind using COX-2 inhibitors in the treatment of acute pain. With selective COX-2-inhibiting analgesics it is possible to inhibit inflammatory processes without favoring the occurrence of clotting disturbances or gastric mucosal lesions. Such an analgesic is available in the form of etoricoxib, which exhibits greater COX-2 selectivity than other coxibs so far approved. Etoricoxib has mainly been used for the treatment of pain associated with osteoarthritis and rheumatoid arthritis pain and for chronic pain (lower back pain). However, coxibs have also been used with impressive results in the treatment of acute peri- and postoperative pain. Thus, a 50 mg preoperative dose of rofecoxib not only significantly decreased the postoperative need for analgesics but also reduced postoperative pain.