Drug eruption to Metamizol-Na

We report on a male patient who received during hemorrhoidal-surgery pre-, peri- and postoperative different drugs. Within 90 minutes he developed a m aculopapular eruption. For clarification we carried out skin tests (prick, intracutaneous, epicutaneous) with analgetic-, antiphlogistic- and local an aesthetic agents. By skin tests we could not demonstrate immediate- or dela yed-type-allergy to the increminated drugs. The causative drug Metamizol-Na could be identified by oral challenge.