This simple test evaluates
the speed in which the colon moves things through.
It is used in the evaluation of chronic constipation.
It consists of orally ingesting many tiny plastic
markers; these markers can be seen on a standard
abdominal X-ray. The person doing test does not
take any laxatives, colon stimulants, suppositories,
or enemas for five days following the ingestion of
the markers. X-rays are used to follow the markers
course through the bowel.