Update on COX-2 NSAIDs.

Sounds like alphabet soup. But, in fact, it is the latest category of pain control (see Running & FitNews, March 1999), significant for runners because these drugs provide anti-inflammatory pain relief without the high risk for stomach problems of the first generation NSAIDs like ibuprofen. The old NSAIDs inhibit two kinds of enzymes COX-1 (that protect the stomach and kidneys) and COX-2 (transmit pain messages and contribute to inflammation). The new COX-2 NSAIDs were thought to just inhibit pain and inflammation.

The good news is that a new study published in the Archives of Internal Medicine compared the efficacy and tolerability of the old with the new--ibuprofen (COX-1 and -2) and rofecoxib (COX-2 only). In a double blind trial of 809 adults with osteoarthritis, patients were randomized to one of four different groups--placebo, rofecoxib 12.5 mg, rofecoxib 25 mg, and ibuprofen 800 mg three times a day. Both doses of rofecoxib and the ibuprofen effectively reduced pain as compared to placebo.

The bad news is that in a review of the research on the COX-2 inhibitors, it seems they may have the same negative effect on kidney function as older NSAIDs, adversely affecting renal function, disturbing sodium and potassium balance, and impairing the work the kidneys do. Publishing in the American Journal of Medicine, authors found that the COX-2 NSAIDs have the same effect on kidney function as the older drugs. While not so important in young, healthy individuals, it can be very significant for patients with high blood pressure, kidney problems, or other health issues.

In another study published in Annals of Internal Medicine, the COX-2 inhibitor rofecoxib was compared to indomethacin, confirming that these drugs reduce kidney function. In two different randomized, crossover, placebo-controlled trials, 75 older patients were given two different doses of rofecoxib, indomethacin, or placebo. The results of the study showed both types of drugs to have similar adverse effects on kidney function. The authors conclude that these problems are likely among both kinds of NSAIDs. The new drugs are not a panacea for osteoarthritis, nor are they risk-free, but they have solved some of the problems associated with NSAIDs since gastrointestinal side effects are reduced. For sports injury pain, always consider rest and ice as your first line of defense.

(Archives of Internal Medicine, 2000, Vol. 160, No. 12, pp. 1781-1787; American Journal of Medicine, 1999, Vol. 107, No. 6A, pp. 65S-71S; Annals of Internal Medicine, 2000, Vol. 133, No. 1, pp. 1-9)