PENICILLIN CONCENTRATION IN SALIVA AND ITS INFLUENCE ON BACTERIAL INTERFERENCE

The aim of the investigation was to study the influence of various penicillin levels on the interference between alpha- and beta-streptococci based on antibiotic levels registered after oral intake of penicillin tablets. It was found that penicillin was released from ordinary sugar coated tablets already in the mouth resulting in concentrations in saliva above the MIC of most penicillin sensitive microorganisms during the first 2 min. This was followed by a decrease of the alpha-streptococcal flora. It was also shown that penicillin levels above the MIC of beta-streptococci but below that of the alpha-strains. At this latter level a synergistic effect between penicillin and interfering alpha-streptococcal strains could be demonstrated.