Fourteen patients suffering from bacterial endocarditis due to a streptococcus or staphylococcus were treated using a combination of amoxicillin per os in a dose of 1 gram every 2 or 3 hours and gentamicin in a dose of 60 mg intramuscularly every 6 or 8 hours. Two patients failed to tolerate amoxicillin, which had to be replaced by penicillin G. Two others, after a period of improvement, relapsed and were cured by the substitution of penicillin G given intravenously, in place of amoxicillin. The ten remaining patients were cured after a normal period of time had elapsed. Two of them were even treated at home. Bactericidal powers of serum obtained by the combination were satisfactory at between 1/16 to 1/4096 one hour after the administration of the antibiotics. This therapeutic protocol is thus effective, and has the advantage of improving the patient's comfort. It should nevertheless be reserved for use against sensitive organisms in patients without digestive problems, the bactericidal power of the serum being verified.