Codeine challenge in chronic urticaria patients.

Prieto-Lastra et al described three patients who developed adverse reactions after receiving codeine. It is known that codeine can induce direct mast cell degranulation and therefore non-IgE mediated reactions. Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequent cause of urticaria and patients with chronic urticaria can present worsening of symptoms with their use. One alternative for these patients is the use of paracetamol, which sometimes is associated with codeine for treatment of more severe pain. We performed 25 controlled oral challenges with 30 mg codeine in patients with chronic urticaria who reported exacerbation with multiple NSAIDs. Neither patient presented adverse reactions. A week later the same patients were submitted to oral challenge with 30 mg codeine associated with 500mg paracetamol. One patient (4 %) developed urticaria 24 hours after drugs intake. Although the present study shows some degree of safety, it is not possible to state that these chronic urticaria patients will not present adverse reactions to codeine in the future. Large and long-term studies are necessary before widespread utilization of codeine in chronic urticaria.