Background:

The cyclooxygenase-2 inhibitors are usually recommended as a safe alternative in patients with multiple hypersensitivity to nonsteroidal antiinflammatory drugs. Nevertheless, both immediate and delayed hypersensitivity reactions have been described, and the possibility of cross-reactivity with sulphonamides.

Case report:

A 66-year-old patient who, after taking a celecoxib tablet, presented with latency of several hours a skin reaction. Previously, he had presented a minor reaction during treatment with etoricoxib without establishing the correlation at that time. The patient underwent an allergological study by means of skin tests with negative results and an oral challenged test with etoricoxib with positive results. Tolerance to sulfonamides was proven.

Conclusion:

We present a singular case of a cross-reactivity skin reaction to etoricoxib and celecoxib, suggesting the need to perform challenge tests to confirm the tolerance or not of each drug before allowing their use. On the contrary, trimethropim/sulfamethoxazole could be safely used in our patients, if needed.