Claims that the drugs, known as selective COX2 inhibitors, caused fewer gastrointestinal problems than traditional arthritis drugs led to an increase in their use, but the research on which they were based was criticised.
Two studies in this week's BMJ, however, show that the risk of gastrointestinal complications associated with selective COX 2 inhibitors is lower than that associated with conventional non-steroidal anti-inflammatory drugs (NSAIDs).
In the first study researchers in Oxford reviewed all trials of the safety and effectiveness of celecoxib, a COX 2 inhibitor used in the treatment of rheumatoid arthritis and osteoarthritis. It was found to be as effective as other NSAIDs and less likely to cause problems such as ulcers.
In the second, researchers in Toronto compared the rates of upper gastrointestinal haemorrhage in elderly users of COX2 inhibitors with those of users of other NSAIDs and a group not using NSAIDs at all. They found that the risk of haemorrhage with the COX2 inhibitors was significantly lower than with conventional NSAIDs. In users of celecoxib, the risk was as similar to that of the group not using NSAIDs at all.
In an accompanying editorial, Dr Roger Jones welcomes the findings but points out that many questions remain unanswered. Neither study comments on death rates and it may not be appropriate to view COX 2 inhibitors as a homogeneous group. More research is needed before doctors can make rational decisions about the drugs, he concludes.