ABSTRACT
This study was undertaken to investigate the response of non-immunologic contact urticaria(NICU) test before and after ingestion of cyclo-oxygenase inhibitors such as naproxene, ibuprofen and mefenamic acid. Forty patients who showed positive reaction to 5% benzoic acid (BA) in petrolatum by 20 minutes closed patch test were chosen and divided into 3 groups. Group I was consisted of 13 patients who were taken naproxene 250mg bid, group II, 14 patients, taken ibuprofen 600mg bid, and group III, 13 patients, taken mefenamic acid 500mg bid. All the patients were tested with 5%, 2.5%, 1%, 0.5% and 0.1% BA in petrolatum using Finn chamber on Scanpor tape on the right arm before medication and next day on the left arm after medication of each day. Mefenamic acid did not show any significant differences before and after ingestion of drug. Naproxene reduced reaction about half of patients. Ibuprofen reduced reaction in almost all patients and blocked reaction completely in 9 of 13 patients. This results suggested that there was no correlation between blocking effect to BA induced contact urticaria and so called anti-inflammatory potencies of naproxene and ibuprofen, and that NICU by BA is partly mediated by prostaglandins(PG) or mediated by other mediators, which were potentiated by PG, except histamin.