Objective To evaluate the positivity of challenge tests of patients suspected of
chronic inducible urticaria and the response to treatment. Methods A retrospective study of electronic medical records of patients suspected of
chronic inducible urticaria. All patients were submitted to challenge tests with triggering stimuli, according to the clinical history and, subsequently, the response to
drug treatment was evaluated. Results A total of 191 patients with suspected
chronic inducible urticaria were included. It was confirmed in 118 patients and 122 positive tests (4 patients with 2 different positive tests). Most had
dermographic urticaria (70.3%), followed by
cholinergic urticaria (17.8%). Regarding treatment, 28% responded to
antihistamine in licensed doses, 34.7% with increased doses, 9.3% responded to the addition of another medication. The concomitance of
chronic inducible urticaria and
chronic spontaneous urticaria was found in 35.3% of patients, being more frequent in females, with longer time to control symptoms and higher frequency of
cholinergic urticaria. Conclusion The confirmation of
chronic inducible urticaria in patients with this suspicion, after challenge tests, was high. There was a good response to
antihistamine. In the concomitance of
chronic spontaneous urticaria, longer time to control symptoms and higher frequency of
cholinergic urticaria were observed.