NSAIDs are estimated to be responsible for up to 25% of all reported adverse drug reactions, ranging from urticaria and angioedema to asthmatic attacks and anaphylactic shock. This condition is problematic for both the patient who is frightened to use NSAIDs and the physician prescribing these drugs. Five hundred and ninty-six patients admitted to our clinic between January 1991 and January 2002 and diagnosed with analgesic intolerance were prospectively enrolled in the survey. A standard questionnaire was filled-in for all the patients. The mean age was 40.3 +/- 12.8 years and 71.8% of the group were females. The most commonly reported intolerance was to aspirin (57.7%), followed by metamizole (47.3%). The most common reason for ingesting an analgesic was headache (63.8%). The three most common accompanying conditions were bronchial asthma (46.1%), perennial rhinosinusitis (45.8%) and antibiotic allergy/intolerance (19%). Eight hundred and seventy-seven oral provocation tests were performed to 380 patients and at least one safe alternative was determined for each patient who was not able to use any analgesic. Analgesic intolerance seems to be an important health problem. The first action to be taken is avoidance of the offending NSAID and suggesting safe alternatives for which the most reliable method is the oral provocation tests.