Activity of tetracycline, doxycycline, and minocycline against methicillin-susceptible and -resistant staphylococci.

Tetracycline, doxycycline, and minocycline were evaluated for their antibacterial activity against methicillin-susceptible and -resistant isolates of Staphylococcus. At clinically achievable levels both doxycycline and minocycline were more active than tetracycline against methicillin-susceptible organisms. Tetracycline and doxycycline had no activity against methicillin-resistant staphylococci, whereas minocycline at 2 mug/ml inhibited six of 13 strains and, at 3 mug/ml, 10 of 13 strains.