Bextra is a sulfonamide drug and can cause anaphylactic shock in people who are allergic to sulfa drugs. The labeling did not initially indicate that Bextra was a sulfa drug and many allergic reactions, some of them life-threatening, occurred before the labeling was changed.

G. D. Searle & Co., which was bought by Pfizer Inc., initially applied for permission to market the drug to treat acute pain, but that indication was not approved by the FDA. Although the agency did not initially release the clinical trials that led to the rejection, they were eventually published and showed an excess number of adverse effects, including heart attacks and strokes, associated with the drug.

Although the data form the study have not been published, the product warning label required by FDA says that there were 13 deaths out of 13,174 patients treated for 28 weeks, compared to four deaths among 13,179 patients receiving a placebo. The risk was higher in blacks than in whites, but data were not presented.