Hypersensitivity to non-β-lactam antibiotics.

Most allergic reactions to antibiotics are caused by β-lactam antibiotics; however non-β-lactam antibiotics are also capable of causing both immediate allergic reactions as well as late-type reactions to these drugs. This is especially true for fluoroquinolones and sulfonamides. Of these, the combination of sulfamethoxazole with trimethoprim (Cotrimoxazol, e.g., Bactrim) is most important. However, there are certain types of reactions to non-β-lactam antibiotics that are not associated with β-lactam antibiotics. These include photosensitivity to sulfonamides, tetracyclines, and fluoroquinolones as well as different patterns of drug metabolism and associations with HLA alleles that may influence their prevalence. This review is focused on recent findings regarding the pathogenesis of allergic reactions to non-β-lactam antibiotics.