Suspected antibiotic hypersensitivity in children is a frequent reason for consultation. Skin test performance and drug provocation test (DPT) duration are controversial issues. The objective of this study was to assess the effectiveness of diagnostic tests used in the study of antibiotic hypersensitivity and to estimate an optimal duration for DPT. Sixty-two children with a suspected hypersensitivity reaction to antibiotics were studied. Skin tests were performed on all patients. In the case of negative results, DPTs were performed for a duration similar to the time elapsed from the start of treatment until the onset of the reaction. The frequency of antibiotic hypersensitivity in the study population was 8.1% (5 of 62). Only 1 patient showed positive skin tests. The other allergic patients were diagnosed by DPT, which reproduced the reaction within the first 6 hours in all but one of them. Shortening DPT duration may decrease the sensitivity of the test for the diagnosis of non-IgE-mediated hypersensitivity; however, it should be considered as an opportunity to reduce the resulting microbial resistances.