Statistical analysis of serum metronidazole levels in patients receiving the drug mainly by suppository

Metronidazole administered by the rectal route has been shown to be clinically effective in reducing the incidence of post-operative infection in patients undergoing abdominal surgery. Only 4 out of 38 patients receiving suppositories post-operatively had serum metronidazole levels below 6 μg/ml at the time of blood sampling, and all had levels above an MIC of 1. 6μg/ml at the time of blood sampling. The computer-calculated line of best fit suggested that the mean serum metronidazole level of the patient population studied exceeded, for the major part of the treatment period, a value of 6 μg/ml.