To evaluate whether atopy is a risk factor for systemic reactions to hymenoptera stings, we compared the atopic status of two groups of subjects. The first group included 93 patients (59 males), mean (+/- SD) age: 42.3 +/- 17.2 yrs with a history of anaphylactic reactions to hymenoptera stings. The second was a control group of 712 subjects (379 males), mean (+/- SD) age: 42.0 +/- 9.6 years recruited at a public health care center. The protocol included a standardized questionnaire about symptoms suggestive of atopy, i.e. medical diagnosis of asthma, perennial rhinitis or hay fever, and skin tests to common aeroallergens, i.e. house dust mites, cat danders, and grass pollens. The percentage of subjects with atopic symptoms was comparable in the two groups (32.2% for the patient group and 28.5% for the control group). Similarly, 22.6% of patients and 36.8% of controls exhibited at least one positive skin prick test. Lastly, 15.1% of patients and 18.5% of controls (a nonsignificant difference) had at least one symptom of atopy and at least one positive skin test. These findings show that atopy is not a risk factor for systemic reactions to hymenoptera stings.