A randomised trial to investigate X-prep, oral mannitol and colonic washout for double-contrast barium enema.

Three methods of bowel preparation used prior to double contrast barium enemas were compared by a randomised trial in 60 patients. Evaluation was by radiological review and from a patient questionnaire. The preparations included X-Prep liquid with colonic washout, oral mannitol alone and oral mannitol with colonic washout. Adequacy of preparation as judged by faecal residue was significantly better after X-Prep than in either group receiving mannitol. The more severe purgation with mannitol did not result in better clearance of the large bowel and the addition of a colonic washout to mannitol did not reduce faecal residue. Side-effects and adverse comments were more common after mannitol. Diarrhoea was significantly less after X-Prep than after mannitol.