Metronidazole (Flagyl) is a medication that treats infections caused by bacteria or parasites. You can take this tablet or capsule by mouth. To reduce the development of drug-resistant bacteria and maintain the effectiveness of FLAGYL® and other antibacterial drugs, FLAGYL® should be used only to treat or prevent infections that are. Flagyl, Flagyl ER, and Flagyl Injection (metronidazole) are antimicrobial drugs used to treat bacterial vaginosis, trichomonas, amebiasis, and anaerobic bacterial infections. Metronidazole injection is used to treat serious bacterial infections in different areas of the body. It is also used to prevent infections in the bowels before and after surgery for some patients. Find patient medical information for Metronidazole (Flagyl, Likmez) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings 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] Flagyl is an antibiotic that is used to treat bacterial infections of the vagina, stomach, liver, skin, joints, brain and spinal cord, lungs, heart, or bloodstream. Metronidazole belongs to the class of medicines known as antibiotics. It works by killing bacteria or preventing their growth. However, this medicine will not work for colds, flu, or other virus infections. This medicine is available only with your doctor's prescription. Flagyl (metronidazole) is not usually used to treat a typical urinary tract infection (UTI), such as uncomplicated bladder infection (acute cystitis). Most uncomplicated UTIs are caused by aerobic bacteria like Escherichia coli that are not reliably covered by metronidazole. Flagyl, or metronidazole, is an antibiotic medication used to treat various bacterial and parasitic infections, including bacterial vaginosis, trichomoniasis, giardiasis, amoebiasis, and certain anaerobic bacterial infections [ 1 ].