Clinical efficacy of Daikenchuto (DKT: TJ-100) for gastrointestinal symptoms in patients with history of colorectal cancer surgery; crossover study - Gastrointestinal transit time as an indicator -

Interventions: A group: Oral administration of Daikenchuto (15g/day t.i.d. before meals) for 28 days. Thereafter non-treatment for 28 days. B group: Non-treatment for 28 days. Thereafter oral administration of Daikenchuto (15g/day t.i.d. before meals) for 28 days. Primary outcome(s): 1)total number of elimination of the radiopaque markers 2) oro-cecal transit time 3) GSRS (Japanese Version) Score 4) VAS 5) GVS Study Design: Cross-over Randomized