Whole bowel irrigation was originally developed to cleanse the large bowel before surgery or colonoscopy. Initially a solution of sodium chloride, potassium chloride, and sodium bicarbonate was used but this electrolyte solution was shown to be absorbed by the body, sometimes leading to complications. To solve this problem a specialized irrigation fluid was developed consisting mainly of an iso-osmolar solution of macrogol. With the macrogol solution there is negligible fluid or electrolyte absorption and several studies have shown the overall safety of the procedure. Whole bowel irrigation was also suggested as a possible treatment for toxic ingestions. WBI has the effect of mechanically flushing the ingested poison out of the gastrointestinal tract before it can be absorbed into the body. A study in 1987 provided evidence that whole bowel irrigation is an effective and safe gastrointestinal decontamination procedure for acute poisoning. Its common administration for toxic ingestions has been largely replaced with that of activated charcoal.
