Parecoxib (parecoxib sodium) is an injectable pro drug of valdecoxib, which is a potent and selective inhibitor of cyclo-oxygenase-2. Intravenous (IV) or intramuscular (IM) parecoxib >20 mg has analgesic activity superior to that of placebo and similar to that of IV or IM ketorolac 30 or 60 mg well controlled trials in patients with postoperative dental pain (n = 304 to 457). In a well controlled trial (n = 202), IV parecoxib 20 or 40mg showed analgesic activity greater than that of placebo and IV morphine 4mg and similar to that of IV ketorolac 30 mg following gynaecological surgery Following orthopaedic surgery, the analgesic activity of IV parecoxib 20 or 40mg was similar to that of IV ketorolac 30 mg and superior to that of IV morphine 4 mg or placebo in well controlled trials (n = 175 and 208). IV parecoxib (40 mg twice daily for 7 days) produced significantly fewer gastrointestinal erosions and/or ulcers than ketorolac (15 mg 4 times a day for 5 days) in healthy volunteers in a well controlled trial; effects on upper gastrointestinal mucosa were similar for parecoxib and placebo. Parecoxib is well tolerated after dental, gynaecological or orthopaedic surgery. The most common adverse events irrespective of treatment (parecoxib, ketorolac or placebo) after dental surgery were nausea, alveolar osteitis, dizziness and headache. Nausea, abdominal pain, headache, abdominal fullness, dizziness, back pain, fever, hypoactive bowel sounds, vomiting, tachycardia, somnolence, abnor mal breath sounds and pruritus occurred in > or = 10% of parecoxib recipients after gynaecological surgery. Similar results were seen in placebo recipients.