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Metronidazole and Tinidazole


Brian J. Werth

, PharmD, University of Washington School of Pharmacy

Last full review/revision Jul 2020| Content last modified Jul 2020
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Metronidazole is an antibiotic Overview of Antibiotics Antibiotics are drugs used to treat bacterial infections. They are ineffective against viral infections and most other infections. Antibiotics either kill microorganisms or stop them from reproducing... read more used to treat pelvic, abdominal, soft-tissue, gum, and tooth infections and abscesses in the lungs or brain. It is also the preferred drug for certain protozoal infections, such as amebiasis Amebiasis Amebiasis is an infection of the large intestine and sometimes the liver and other organs that is caused by the single-celled protozoan parasite Entamoeba histolytica, an ameba. The amebas may... read more , the intestinal infection giardiasis Giardiasis Giardiasis is an infection of the small intestine caused by the single-celled protozoan parasite Giardia. The main symptoms are abdominal cramping and diarrhea. People may have abdominal cramping... read more , the vaginal infection Trichomonas vaginitis Trichomonas Vaginitis Trichomonas vaginitis is a vaginal infection due to the protozoa Trichomonas vaginalis. Trichomonas vaginitis is usually sexually transmitted. It can cause a green or yellow discharge, which... read more , and the bacterial infection bacterial vaginosis Bacterial Vaginosis (BV) Bacterial vaginosis is a vaginal infection that occurs when the balance of bacteria in the vagina is altered. Women who have a sexually transmitted disease, who have several sex partners, or... read more . Tinidazole is a related antibiotic used primarily to treat those same protozoal infections and bacterial vaginosis.

Metronidazole works by disrupting the production of genetic material by bacteria. As a result, the bacteria die. Tinidazole works in a similar way.

Metronidazole is usually taken by mouth but can be given intravenously. Tinidazole is taken by mouth.

Metronidazole and tinidazole can interfere with alcohol metabolism and can cause unpleasant side effects similar to those of a hangover including nausea, vomiting, flushing, and headache. Alcohol should be avoided while taking metronidazole or tinidazole and for 3 days after the last dose.


Use of Metronidazole or Tinidazole During Pregnancy and Breastfeeding

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