What is "antimetabolite"

n. (context medicine English) Any substance that competes with, or inhibits the normal metabolic process, often by acting as an analogue of an essential metabolite

n. an antineoplastic drug that inhibits the utilization of a metabolite

An antimetabolite is a chemical that inhibits the use of a metabolite, which is another chemical that is part of normal metabolism. Such substances are often similar in structure to the metabolite that they interfere with, such as the antifolates that interfere with the use of folic acid. The presence of antimetabolites can have toxic effects on cells, such as halting cell growth and cell division, so these compounds are used as chemotherapy for cancer.