Octreotide acetate induces fasting small bowel motility in patients with dumping syndrome

Abstract

The long acting somatostatin analogue octreotide acetate has been effective in the treatment of early dumping syndrome. We hypothesized that this may be related to its effects on inhibiting gastric emptying and delaying intestinal transit. To study the effects of octreotide acetate on intestinal motility in patients we carried out a randomized, double-blinded study using a subcutaneous injection of either octreotide acetate (100 μg) or placebo given 20 min prior to ingestion of a high carbohydrate “dumping” meal in six patients with known severe dumping syndrome. Prior to each study a multilumen polyethylene tube was inserted into the efferent limb to study small intestinal contractions using low compliance pneumo-hydraulic water-perfused manometry. Octreotide acetate prevented dumping symptoms in all six patients and induced the appearance of migrating myoelectric complexes (MMC) characteristic of interdigestive motility. After ingestion of the dumping meal the postprandial “fed” motility pattern lasted for 141 ± 9 min while after octreotide acetate the fed motility lasted for 29 ± 5 min ( P < 0.03). The vigor of the fed motility pattern as measured by the motility index (MI = log e{sum of amplitudes × No. of contractions + 1}) was lower after octreotide acetate than after placebo (15.1 ± 0.1 vs 13.4 ± 0.2, P < 0.03). The induction of fasting MMC motility pattern and reduction in the duration and vigor of fed motility may explain the symptomatic relief these patients obtained with octreotide acetate. It is not known whether the induction of the MMC is a direct effect of octreotide acetate or secondary to the concomitant inhibition of peptide release (neurotensin, insulin, glucagon, pancreatic polypeptide) that has been demonstrated in earlier studies.