Infective endocarditis is a rare condition with an incidence of less than 10 per 100 000 population/year. It is, however, associated with a high mortality and morbidity. Accepted clinical practice has been to use antibiotic prophylaxis in those at risk of infective endocarditis undergoing dental and certain non-dental interventional procedures, in the belief that this may prevent its development. The effectiveness of such antibiotic prophylaxis in humans is, however, not proved1 and the recent American Heart Association guideline2 recommends a much more limited role for antibiotic prophylaxis against infective endocarditis. This article summarises the most recent guidance from the National Institute for Health and Clinical Excellence (NICE) on antibiotic prophylaxis against infective endocarditis.3

In summary, this guideline recommends that antibiotic prophylaxis to prevent infective endocarditis should not be given to adults and children with structural cardiac defects at risk of infective endocarditis undergoing dental and non-dental interventional procedures. The basis for this recommendation is:

• There is no consistent association between having an interventional procedure, dental or non-dental, and the development of infective endocarditis.

• Regular tooth brushing almost certainly presents a greater risk of infective endocarditis than a single dental procedure because of repetitive exposure to bacteraemia with oral flora.

• The clinical effectiveness of antibiotic prophylaxis is not proved.

• Antibiotic prophylaxis against infective endocarditis for dental procedures is not cost effective and may …