There are two situations when antibiotic prophylaxis is recommended. The first is associated with procedures known to be followed by high rates of bacteraemia, involving organisms prone to cause endocarditis. These include oesophageal dilatation, variceal sclerotherapy and laser therapy in the upper gastrointestinal tract. As bacteraemia following these procedures is usually harmless in average risk patients antibiotic prophylaxis is recommended only for a patient with a lesion susceptible to endocarditis or one who is at increased risk of symptomatic bacteraemia due to neutropenia or immunosuppression. In most cases parenteral amoxycillin and gentamicin is recommended plus metronidazole for neutropenic patients. Vancomycin or teicoplanin replace amoxycillin in a case of allergy. The second situation concerns procedures with a high incidence of local infection or which may lead to serious sepsis. These include therapeutic retrograde cholangiopancratography and percutaneous endoscopic gastrostomy where antibiotic prophylaxis is recommended even in average risk patients. Several antibiotics are recommended including oral ciprofloxacin or parenteral gentamicin or quinolone for ERCP and amoxycillin for PEG or cephalosporin or ureidopenicillin for both.