cathartic

1. (medicine) A laxative.Examples: "The disease was regarded as pneumonia so far advanced that suppuration seemed to have supervened; bleeding, blisters, expectorants, and cathartics diminished the symptoms; the pulse continued frequent, hard, full, but always regular."; "As Jan McTavish notes, when the physician diagnosed the headache's origins in the digestive system, particularly constipation, the antidote might entail cathartics (substances that accelerate defecation) or emetics (inducers of vomiting) and other regulators of the digestive process."