Patients with chronic urticaria frequently experience flares of hives following the ingestion of chemically unrelated nonsteroidal anti-inflammatory drugs (NSAIDs). The pathogenic mechanism of these reactions is based on cyclooxygenase-1 (COX-1) enzyme inhibition. In most cases, nonselective NSAIDs, which inhibit both COX-1 and COX-2, are responsible for such adverse reactions; in contrast, analgesic and anti-inflammatory drugs exerting limited inhibition on COX-1 are generally better tolerated by these patients. This study aimed to detect tolerability of etoricoxib, a selective COX-2-inhibiting drug, in patients with chronic urticaria with a history of NSAID intolerance. Single-blind, placebo-controlled oral challenges with increasing doses of etoricoxib were carried out in 17 adult patients with chronic urticaria exacerbated by NSAID. All patients tolerated the drug at therapeutic doses. The study suggests that etoricoxib, with its favourable COX-1/COX-2 ratio, is well tolerated by patients with chronic urticaria exacerbated by NSAID intolerance.