Quinolones are broad spectrum antibiotics that are intensively used and can induce immediate- and delayed-type hypersensitivity reactions, either IgE or T-cell mediated, in about 2-3% of treated patients. OBJECTIVE To better understand how T cells interact with quinolones to produce the hypersensitivity and to describe the possible prevention of the reactions. METHODS We search in PubMed for quinolones and adverse reactions naming each one of the therapeutics in use and the possible hypersensitivity reactions e.g., anaphylaxis, drug-induced delayed reactions, and hypersensitivity syndrome reactions. We also performed a search on organ-specific hypersensitivity reactions including cutaneous reactions, hepatic reactions, and renal reactions. RESULTS Our data show that T cells are involved in delayed immune reactions to quinolones and that cross-reactivity among the different quinolones is frequent. The predictive tests for quinolone-induced hypersensitivity should be used in patients before they are given the medication. CONCLUSIONS Early identification of the mechanism of toxicity, quantitative assessment using laboratory tests, analysis of risk factors for patient susceptibility to the quinolones, and possible drug-drug interactions may lead to appropriate patient selection for therapy, monitoring the injury early and discontinuation of the therapeutic agent.