Daikenchuto (TU-100) is a traditional Japanese (
Kampo) medicine used to treat postoperative
ileus.
TU-100 dose dependently increases gastrointestinal (GI) motility by modulating
cholinergic and serotonergic mechanisms in animal studies. The aim of this study was to evaluate the effects of orally administered
TU-100 on GI and colonic transit and bowel function in healthy humans. In a randomized, parallel-group, double-blind, placebo-controlled, dose-response study, 60 healthy subjects were randomly assigned to placebo or
TU-100 2.5 g or 5 g tid ingested immediately before meals for 5 consecutive days. We measured GI and colonic transit by validated scintigraphy and stool frequency and consistency by daily diaries of bowel function. There were overall treatment effects on colonic filling at 6 h without any significant differences between each dose of
TU-100 and placebo. There tended to be overall treatment effects on ascending colon (AC) emptying half-time; the
TU-100 (7.5 g/day) treatment significantly accelerated AC emptying compared with placebo. There were numerically higher values of GC24 (which reflect overall colonic transit) with both doses of
TU-100, but these changes were not statistically significant. There were no significant overall treatment effects on gastric emptying or stool frequency and consistency. One subject, who received 7.5 g/day of
TU-100, had elevated
creatine phosphokinase following the study.
TU-100 (7.5 g/day) significantly accelerated AC emptying. Further randomized controlled trials in patients with functional
constipation or
irritable bowel syndrome with
constipation are warranted to evaluate the clinical efficacy of
TU-100 in these disorders.