1.   Dialysis bags were inserted per rectum for two hours and then removed.

2.   In vivo rectal dialysis reflects epithelial transport if the dialysis bag is in close contact with the rectal mucosa, and does not equilibrate with faeces or fluid.

3.   The possibility that the contents of the dialysis bag may change if suspended in a solution mimicking diarrhoeal stool water was also examined.

4.   Secondly, dialysis bags with the two test fluids were suspended for an hour in a solution of composition similar to cholera stool.