Anti-anaerobic activity of antibacterial agents.

The first very effective bactericidal anti-anaerobic drug was metronidazole, introduced in clinical practice in the early 1980s. Sometimes penicillin G and chloramphenicol were used successfully in some anaerobic infections. However, this result was most likely due to Gram-positive anaerobic infections (e.g., Clostridium perfringens). Very rapidly, the anti-anaerobic armamentarium was extended with clindamycin, cefoxitin, imipenem and co-amoxyclav or piperacillin-tazobactam. The resistance rate to metronidazole and imipenem remains low but clindamycin has seen an importance decrease in bacterial susceptibility. New additional drugs could be very helpful to overcome resistance and adverse events. The novelties in this field are fluoroquinolones, which exhibit a good activity against Gram-positive cocci and anaerobes.