Analgesic intolerance (AI) which is classically known as a disease of the middle-aged adults, not uncommonly starts in childhood. In this study we sought to identify the characteristics of childhood onset Al and evaluated its association with the development of asthma. Among 729 analgesic intolerant patients followed in our institution between January 1991 and July 2004, 50 (16 mate, 34 female, 6.8% of the total Al population) had history of Al starting before the age of 18. The prevalence of asthma was 24% in childhood and increased to 40% during adulthood. Atopy was more common in patients with bronchial asthma (p < 0.05). The mean (+/- SD) age of onset for asthma (18.6 +/- 9.7years) was significantly greater than the onset of both rhinitis and Al (13.0 +/- 6.5 and 13.2 +/- 4.0 years, respectively). This finding is different than the chronology of events reported in the literature for adult onset Al patients, in which rhinitis and asthma usually precede the development of Al. The presence of such a difference in the sequence of disease patterns may be a clue for the pathophysiologic differences underlying childhood and adult onset Al. The role of childhood onset Al as a risk factor for developing for asthma in adulthood should be further assessed in prospective patient cohorts. (c) 2008 Elsevier Ltd. All rights reserved.