Metronidazole in anaerobic infections: a review of its activity, pharmacokinetics and therapeutic use.

Metronidazole which has been widely used for many years in the treatment of trichomoniasis, amoebiasis and giardiasis, has recently been shown to be active against anaerobic bacteria. Serum, cerebrospinal fluid and tissue concentrations bactericidal for Bacteroides species are attained after usual dosages given orally or intravenously or higher dosages given rectally (suppository). Prospective studies have demonstrated that the addition of metronidazole to regimens for pre-operative bowel preparation, decreases the frequency of postoperative infection and eliminates anaerobic infection. Similarly, anaerobic infection after acute appendicectomy or hysterectomy has been virtually eliminated by metronidazole given before and up to 1 week after surgery. Metronidazole has been successfully used in the treatment of anaerobic infections of the chest, head, gastrointestinal and female genitourinary tract, and of anaerobic septicaemia and bacteraemia. Metronidazole is the most active agent available against obligate anaerobes and is likely to be of major value in the treatment of serious infections due to these organisms. Although the absence of formal comparative trials in many areas of use makes it difficult to clearly state the relative therapeutic efficacy of metronidazole, compared with other drugs such as clindamycin, chloramphenicol or penicillin, it is nevertheless a very effective agent in the treatment and prevention of anaerobic infections.