In vitro evaluation of clindamycin in combination with oxacillin, rifampin, or vancomycin against Staphylococcus aureus.

In a study of antibiotic combinations of clindamycin with rifampin, oxacillin, or vancomycin using the time kill-curve method, the combination of clindamycin and rifampin were sometimes synergistic (5 of 15 times), otherwise indifferent and always enhanced killing of fifteen tested Staphylococcus aureus isolates. In contrast, vancomycin and clindamycin or oxacillin and clindamycin were either indifferent or antagonistic (approximately 50%). Vancomycin alone, however, was generally as effective as the combinations of clindamycin and rifampin.