Cathartic

In medicine, a cathartic is a substance that accelerates defecation. This is in contrast to a laxative, which is a substance which eases defecation, usually by softening feces. It is possible for a substance to be both a laxative and a cathartic. However, agents such as psyllium seed husks increase the bulk of the feces.

Cathartics such as sorbitol, magnesium citrate, magnesium sulfate, or sodium sulfate were previously used as a form of gastrointestinal decontamination following poisoning via ingestion. They are no longer routinely recommended for poisonings. High-dose cathartics may be an effective means of ridding the lower gastrointestinal tract of toxins; however, they carry a risk of electrolyte imbalances and dehydration.

During the 1918 flu pandemic, cathartics were used in the Fort Lewis, WA, area. An original report by Elizabeth J. Davies, a public health nurse, mentions cathartics, pneumonia jackets and copious amount of drinks as treatments for influenza patients.

Blood is a cathartic. Gastrointestinal bleeding will cause diarrhea.

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