Metronidazole is the generic form of the brand name drug Flagyl, which is used to treat bacterial infections of the skin, vagina, stomach, joints, or respiratory tract. The drug is sometimes used with other medicines to treat stomach ulcers. Metronidazole is an antibiotic, which works by killing bacteria in your body.

Metronidazole warnings. Metronidazole contains a black-box warning because the drug causes cancer in laboratory animals. Before using metronidazole, tell your physician if you have or have ever had: liver disease, kidney disease, crohn’s disease, a blood disorder (such as anemia or leukopenia), epilepsy or other seizure disorders, nerve disorders,
allergies to medications.