Enteroglucagon concentration in peripheral blood was determined before and after a test meal in 24 morbidly obese patients. Eighteen had jejunoileal bypass, 6 with a 3:1 and 12 with a 1:3 jejunoileal ratio of the functioning segment, and 6 were unoperated. All three groups exhibited an increment of enteroglucagon concentration after the meal. Both the fasting values and the postprandial integrated increments were higher in operated patients than in unoperated patients and higher after 1:3 bypass than after 3:1 bypass. The findings agree with the hypothesis that enteroglucagon secretion is stimulated by exposure of the lower bowel to upper-bowel content, and that the effect of enteroglucagon is, as seen after bypass operation, stimulation of growth and reduction of motility of the intestine.

The pharmacokinetics of ampicillin and prophylthiouracil were studied in 6 and 9 patients, respectively, before and several times up to a year after a shunt operation for extreme obesity. The drugs were given intravenously and orally making it possible to estimate the absolute bioavailability. The bioavailability of propylthiouracil (about 80%) was unchanged by the surgical procedure but the fraction of ampicillin (given as pivampicillin) absorbed decreased from a preoperative value of 109 +/- 44% to 44 +/- 30% 12 months after the bypass operation. Volumes of distribution transiently decreased in the postoperative period for ampicillin. Clearance was initially reduced for both ampicillin and propylthiouracil after operation but returned to normal values a year later. Half-lives of both drugs were unchanged. These results are compared with previous data on pharmacokinetics in intestinal shunt patients and a tabular review is presented. Although no general rules presently emerge from the data available, it seems prudent to closely monitor intestinal shunt patients on drug therapy by both laboratory and clinical methods.