Please consult your physician before taking any medication. Furazolidone (fyoor-a-ZOE-li-done) is used to treat bacterial and protozoal (proe-toe-ZOE-al) infections. It works by killing bacteria and protozoa (tiny, one-celled animals). Some protozoa are parasites that can cause many different kinds of infections in the body. Furazolidone is taken by mouth. It works inside the intestinal tract to treat cholera, colitis, and/or diarrhea caused by bacteria, and giardiasis (jee-ar-DYE-a-siss) . This medicine is sometimes given with other medicines for bacterial infections. Furazolidone may also be used for purposes other than those listed in this medication guide.