Anaphylactic Reaction Induced by Diclofenac.

A case of anaphylactic reaction induced by diclofenac in an 85-year-old woman is reported. The patient collapsed 30 min after oral administration of diclofenac, preceded by sulindac ingestion. Treatment was started immediately, and she recovered quickly. The lymphocyte stimulation test was positive for diclofenac and slightly positive for sulindac. As the etiology of the anaphylactic reaction, it was suspected that diclofenac acted as a challenging antigen in the patient who was already sensitized by sulindac.