Clinical efficacy of 12-h metronidazole dosing regimens in patients with anaerobic or mixed anaerobic infections

Traditional metronidazole dosing regimens utilize an every 8 h dosing strategy to treat anaerobic and mixed anaerobic infections. However, pharmacokinetic data demonstrate that the half-life of metronidazole is 8–12 h and blood levels at 12 h exceed the in vitro minimum inhibitory concentration (MIC) for most anaerobic infections. The primary objective of this study was to evaluate the frequency of clinical cure among patients who received metronidazole every 12 h compared with those who received an every 8 h frequency. Secondary endpoints included duration of antibiotics, hospital length of stay, escalation of antibiotic therapy, microbiologic cure, and mortality