Washout versus non-washout (Picolax) preparation for double-contrast barium enemas.

A non-washout preparation using Picolax in 40 patients, compared with a standard method using washouts in 38 patients, showed no significant difference in the contamination by residual formed or semiliquid faeces, although Picolax was associated with significantly more contamination due to adherent faeces and mucus. The overall differences in contamination were most marked in the transverse colon. Picolax also affected the smooth muscle tone of the bowel wall, causing an increase in 'mucosal crinkling'.