COMPARATIVE EFFICACY OF ORAL DOSES OF CLINDAMYCIN AND ERYTHROMYCIN INTHE PREVENTION OF BACTEREMIA

Two antibiotics, clindamycin and erythromycin, were compared in a doub le-blind trial to test their efficacy in the prevention of post-dental extraction bacteraemia with streptococci in a group of 40 healthy pat ients. Tolerance to the oral doses was tested by questionnaire. Levels of drug in the serum were estimated using a microbiological assay. An in-vitro blood culture system was used as an analogy of the persisten ce of a bacteraemia in the presence of high levels of antibiotic. Isol ates of streptococci were identified to species level. Minimum inhibit ory concentrations of clindamycin and of erythromycin for each isolate were estimated. Results showed satisfactory levels of antibiotics in the blood for activity against oral streptococci. Clindamycin was slig htly more effective than erythromycin in the prevention of post-extrac tion streptococcal bacteraemia but that efficacy was only 45%. Clindam ycin as a single oral dose of 600 mg was well tolerated by patients co mpared with erythromycin 1.5 g.