[Urticaria--angioedema induced by non-steroidal anti-inflammatory analgesics]

Forty-two adult patients had been evaluated with a history of Urticaria and Angioedema (U-AE) associated with ingestion of non-steroidal anti-inflammatory drugs (NSAID). None developed attacks of bronchospasm. None had chronic urticaria. The same reaction was repeated in 36 individuals on at least two different occasions following administration of these drugs. Based on patients'history we distinguished three groups: Group A: twenty-three patients who had presented U-AE with the administration of pyrazolone drugs. Thereafter, sixteen of them had taken aspirin without adverse reactions. Group B: Nine patients in whom aspirin caused U-AE, after three of them had taken pyrazolone drugs without intolerance. The remaining six had not taken analgesic drugs since the last reaction. Group C: Ten patients who had developed U-AE with aspirin as well as with pyrazolone drugs. The objective of our study was the following: 1) to observe tolerance level of these patients to other NSAID different from those which had produced the first reactions. 2) To test to see if the patients who had suffered U-AE by noramidopyrine and aminophenazone tolerated other pyrazolone drugs like sulfinpyrazone and phenylbutazone. 3) To see if reactions are produced with tartrazine in patients who had presented U-AE with pyrazolone drugs, given that this colouring (tartrazine) is a pyrazolone derivative. Skin test (prick and intracutaneous test) with noramidopyrine, phenylbutazone and noramidopyrine metasulphonate MG, were carried out on the patients in group A, group C and 30 normal controls. In all the groups oral challenge tests were performed with progressive doses of naproxen, indomethacin, paracetamol, ciclofenac, mefenamic acid, piroxicam and phenylbutazone. Oral challenge tests were accomplished with aspirin in group A and with propiphenazone in group B. Oral challenge tests with sulfinpyrazone and tartrazine were also performed on various patients in group A and group C. The interval between the administration of progressive doses of a drug was 3 and as half hours and were allowed to pass at least 24 hours before testing other different analgesics. The test was considered positive if cutaneous rash, wheals, AE or hypotension were produced. In this case, the test was halted and 7 days were allowed to pass before continuing the study with a new drug. Based on the oral challenge tests performed, three types of patients could be distinguished: 1) individuals sensitive only to the pyrazolone drugs and who can take with impunity other NSAID.(ABSTRACT TRUNCATED AT 400 WORDS)