Susceptibility of anaerobic bacteria to thiamphenicol

The activity of thiamphenicol, an analogue of chloramphenicol without a nitro group, was compared with that of chloramphenicol against anaerobic bacteria. A plate dilution technique on brucella agar supplemented with laked sheep blood and vitamin K1 was used. Chloramphenicol exhibited slightly greater activity than thiamphenicol in vitro, but the difference was too small to be of potential clinical significance.