Is Flagyl (metronidazole) the same as metronidazole?

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From the Guidelines

Flagyl is essentially the same as metronidazole, as it is the brand name for the generic drug 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 ]. The medication works by stopping the growth of certain bacteria and parasites by interfering with their DNA, ultimately killing them.

Key Points to Consider

  • Metronidazole is available in different forms, including tablets, capsules, creams, gels, and intravenous solutions.
  • Common oral dosages range from 250mg to 500mg taken 2-3 times daily, with treatment duration typically lasting 5-14 days depending on the specific infection being treated [ 1 ].
  • It's crucial to take the full course of metronidazole as prescribed, even if symptoms improve before completion, and to avoid alcohol during treatment and for at least 24 hours afterward, as this combination can cause severe nausea, vomiting, and other unpleasant reactions [ 1 ].
  • The FDA has approved Flagyl 375 mg twice a day for 7 days for the treatment of trichomoniasis based on pharmacokinetic equivalency with metronidazole 250 mg three times a day for 7 days [ 1 ].

Treatment Recommendations

  • For bacterial vaginosis, recommended regimens include metronidazole 500 mg orally twice a day for 7 days, or metronidazole gel 0.75% intravaginally once a day for 5 days [ 1 ].
  • Patients should be advised to avoid consuming alcohol during treatment with metronidazole and for 24 hours thereafter [ 1 ].

From the FDA Drug Label

Metronidazole 250 mg and 500 mg tablets, for oral administration, contain the inactive ingredients: colloidal silicon dioxide, hydroxypropyl cellulose, lactose (anhydrous), microcrystalline cellulose, sodium starch glycolate, and stearic acid. Flagyl is another name for metronidazole, as it is a common brand name for this medication 2.

  • Flagyl and metronidazole are the same medication, with Flagyl being a brand name and metronidazole being the generic name. The FDA drug label for metronidazole confirms that Flagyl is indeed another name for this medication 2.

From the Research

Flagyl and Metronidazole

  • Flagyl is another name for the medication metronidazole 3, 4, 5, 6, 7
  • Metronidazole is a nitroimidazole antibiotic that has a limited spectrum of activity against various protozoans and most Gram-negative and Gram-positive anaerobic bacteria 3
  • It is used to treat a variety of infections, including bacterial vaginosis, trichomoniasis, and pelvic inflammatory disease 4, 5, 6, 7

Uses of Metronidazole

  • Metronidazole is effective against protozoans like Entamoeba histolytica, Giardia lamblia, and Trichomonas vaginalis 3
  • It is also effective against anaerobic bacteria, including Bacteroides and Fusobacterium spp. 3
  • Metronidazole has been used to treat Crohn's disease, Clostridium difficile-induced pseudomembranous colitis, and anaerobic brain abscesses 3

Comparison of Flagyl and Metronidazole

  • Flagyl and metronidazole are the same medication, with metronidazole being the generic name and Flagyl being a brand name 3, 4, 5, 6, 7
  • They have the same mechanism of action, uses, and side effects 3, 4, 5, 6, 7

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Metronidazole for the treatment of vaginal infections.

Expert opinion on pharmacotherapy, 2015

Research

Levofloxacin plus metronidazole in uncomplicated pelvic inflammatory disease: a preliminary study.

European journal of obstetrics, gynecology, and reproductive biology, 2009

Research

Bacterial vaginosis: review of treatment options and potential clinical indications for therapy.

Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 1995

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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