Twelve-hourly dosage schedule for oral and intravenous metronidazole.
Paired samples of blood were examined from 48 patients undergoing major surgery who were receiving metronidazole at a 12-hourly dosage interval, as part of a regimen for prophylaxis or therapy. Twenty-five patients were given 400 mg metronidazole orally twice a day and 23 received 500 mg metronidazole iv twice daily. Assay of the samples demonstrated trough serum concentrations of metronidazole of 3-11 mg/l (mean 5.5 mg/l) and 2-15 mg/l (mean 6.7 mg/l) with the oral and intravenous routes, respectively. The corresponding peak serum concentrations were 10-26 mg/l (mean 17.4 mg/l) and 13-28 mg/l (mean 23.6 mg/l). The trough concentrations are well in excess of the MICs for the majority of obligate anaerobes and thus the 12-hourly regimen achieves and maintains therapeutic serum concentrations of metronidazole.
Earl
P
P
Shotley Bridge General Hospital, Consett, UK.
Sisson
P R
PR
Ingham
H R
HR
D000284:Administration, Oral; D001681:Biological Assay; D006801:Humans; D007275:Injections, Intravenous; D008795:Metronidazole / Q000008:administration & dosage* / Q000493:pharmacokinetics
D008795:Metronidazole