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IntroductionHypersensitivity to beta-lactams remains overestimated. The impact of overdiagnosis or diagnosis by default is significant. Our work aims to describe the allergy assessment approach and its contribution in beta-lactam hypersensitivity de-labeling through a series of patients in the Tunisian population.MethodsCross-sectional study focused on a sample of patients presenting beta-lactam hypersensitivity collected in the allergology “C” department of Mami Hospital in Ariana between January 2007 and June 2022.ResultsNinety-eight patients (37 men, 61 women) with an average age of 37.8 years had a suspected allergy to beta-lactam antibiotics. The most common clinical manifestations included: urticaria (n = 73), angioedema (n = 15), anaphylactic shock (n = 13), dyspnea (n = 34), bronchospasm (n = 9), and digestive issues (n = 47). The drugs were administered via the oral route in 83.3 % of cases. The allergy assessment was conducted on average 5.5 months after the last presumed drug reaction. Prick tests at pure recommended concentrations were positive in 17 cases (17.3 %), while intradermal reactions were positive in 14 cases. An allergy to cephalosporins was observed in 6 cases. The drug provocation tests performed in 65 patients with negative skin tests were positive in 10 cases. At the end of the allergy assessment, a diagnosis of beta-lactam allergy was confirmed in 41 patients (19.3 %).ConclusionBeta-lactam allergy is not uncommon. Beta-lactam skin tests have good diagnostic and predictive value for true beta-lactam allergy.