The Journal of Bone and Mineral Research (June, 2002 17:963), studied the effects of two drugs, Vioxx and Celebrex on bone repair. These drugs are the new generation of anti-inflammatory drugs. These are known as Cox-2 inhibitors; so named because of the inflammatory enzyme that they inhibit. These drugs are often used to ease the pain of broken bones. The irony is that they may inhibit bone repair. Vioxx, of course has been taken off of the market because of a link to cardiac problems.
The old generation of pain killers (like ibuprofen and indomethacin), seemed to only delay bone healing slightly. Studies on rats show these new pain relievers to interfere with bone healing much more severely. Where ibuprofen and indomethacin delay bone healing by one or two weeks in rats (the human equivalent of that is 25 to 50 percent), rats given Vioxx were unable to heal their bones.