Metronidazole is used to treat infections of the reproductive system, gastrointestinal (GI) tract, skin, heart, bone, joint, lung, blood, nervous system, and other areas of the body. It is also used to treat certain sexually transmitted diseases (STDs). Metronidazole is used to treat bacterial infections in different areas of the body. It is also used to treat infections caused by protozoa (eg, trichomoniasis and amebiasis) and infections caused by bacteria that do not need oxygen to survive. Metronidazole is an antibiotic used to treat bacterial and protozoal infections. Side effects of metronidazole can include headaches, taste changes, and nausea. Flagyl (metronidazole) is an antibiotic that can help treat certain infections caused by bacteria or parasites that also cause diarrhea. It is not used to treat most cases of sudden (acute) diarrhea, such as viral “stomach flu” or mild food poisoning. Find patient medical information for Metronidazole (Flagyl, Likmez) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Metronidazole is a prescription antibiotic medication prescribed for the treatment of a variety of parasitic and bacterial infections of the vagina, gynecological area, skin, intra-abdominal cavity, blood, bone, joint, nervous system, and heart. Metronidazole, sold under the brand name Flagyl and Metrogyl among others, is an antibiotic and antiprotozoal medication. [10] It is used either alone or with other antibiotics to treat pelvic inflammatory disease, endocarditis, and bacterial vaginosis. [10] Metronidazole is an antibiotic used to fight bacteria in your body. Learn about side effects, interactions and indications. Metronidazole is an oral medication prescribed for the treatment of various types of infections, including bacterial infections and protozoal infections caused by parasites. Metronidazole may also help treat other inflammations found in the gastric system. Metronidazole is used to treat a certain type of vaginal infection (bacterial vaginosis) in women who are not pregnant. Learn about side effects, drug interactions, dosages, warnings, and more.