Autointoxication is an ancient theory based on the belief that intestinal waste products can poison the body and are a major contributor to many, if not all, diseases. In the 19th century, it was the ruling doctrine of medicine and led "colonic quackery" in various guises. By the turn of the century, it had received some apparent backing from science. When it became clear that the scientific rationale was wrong and colonic irrigation was not merely useless but potentially dangerous, it was exposed as quackery and subsequently went into a decline. Today we are witnessing a resurgence of colonic irrigation based on little less than the old bogus claims and the impressive power of vested interests. Even today's experts on colonic irrigation can only provide theories and anecdotes in its support. It seems, therefore, that ignorance is celebrating a triumph over science.