Β-lactam antibiotic reactions to any β-lactam antibiotic may occur in up to 10% of patients receiving that agent (a small fraction of which are truly IgE-mediated allergic reactions, see amoxicillin rash). Anaphylaxis will occur in approximately 0.01% of patients. There is perhaps a 5%-10% cross-sensitivity between penicillin-derivatives, cephalosporins, and carbapenems; but this figure has been challenged by various investigators. Nevertheless, the risk of cross-reactivity is sufficient to warrant the contraindication of all β-lactam antibiotics in patients with a history of severe allergic reactions (urticaria, anaphylaxis, interstitial nephritis) to any β-lactam antibiotic. A Jarisch–Herxheimer reaction may occur after initial treatment of a spirochetal
Antibiotic use in dentistry prophylaxis to prevent post-operative infections, resulting from bacteraemia, and infective endocarditis was practiced by dentists, especially in patients at high risk (i.e. with heart problems). However, according to new recommendations from the National Institution for Health and Care Excellence (NICE), antibiotic prophylaxis should not be offered for all patients at risk of infective endocarditis. This is due to the ever-increasing antibiotic resistance and there is no or very little evidence to show whether antibiotic prophylaxis is effective or ineffective against post-operative infections. Moreover, it is yet to be established whether the benefits of administering antibiotics prophylactically outweighs the inherent risks,