Absorption of metronidazole suppositories in patients with postoperative ileus.

Thirty-five patients with postoperative ileus were given one g metronidazole suppositories three times daily. The patients were divided into four groups according to the operative procedure. The postoperative bowel motility was assessed as the time at which bowel sounds and evacuation occurred. One group of patients differed significantly from the others with regard to the time taken for the bowel function to become normal. No significant difference existed in the serum concentrations of metronidazole between the groups. Absorption of the first suppository was slower in our patients than in normal subjects, but thereafter concentrations followed the theoretic concentration curve for healthy subjects on the same dose regimen. Steady state, indicating normal absorption, was attained before bowel function returned to normal. The reason for the slower absorption of the first suppository is probably that the patients were confined to bed.