antimotility

adjective

an·​ti·​mo·​til·​i·​ty -mō-ˈtil-ət-ē 

variants also anti-motility

: inhibiting or slowing gastrointestinal motility

The caplets … contain an antimotility agent that relieves the symptoms of diarrhea by slowing intestinal movement.

—James T. Yenckel, The Washington Post

Drugs to improve symptoms, particularly antimotility drugs such as loperamide and diphenoxylate hydrochloride, can reduce the number of stools passed and may be useful in controlling the stool rate with watery diarrhea.

—Herbert L. DuPont, The New England Journal of Medicine