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Compare Gentamicin vs. Flagyl

Head-to-head comparisons of medication uses, side effects, warnings, and more.

Key takeaways

Gentak (gentamicin) and Flagyl (metronidazole) are both antibiotics, but they treat different types of infections and are used in different ways. Gentak (gentamicin) is an aminoglycoside antibiotic used as eye drops or ointment to treat bacterial infections of the eye or eyelid, such as pink eye or blepharitis. It works by blocking bacteria from making proteins they need to survive. On the other hand, Flagyl (metronidazole) is a nitroimidazole antibiotic taken by mouth to treat various bacterial and parasitic infections, including trichomoniasis and bacterial vaginosis. It kills bacteria and parasites by damaging their genetic material. While Gentak is applied directly to the eye and starts working right away, Flagyl is taken orally and can cause side effects like nausea and a metallic taste. Additionally, you must avoid alcohol while taking Flagyl and for three days after, as it can cause a serious reaction. Both medications are available in lower-cost generic forms and require a prescription.

  • Gentamicin
    Metronidazole (Flagyl)
  • Gentamicin
    Metronidazole (Flagyl)

  • Summary of Gentamicin vs. Flagyl

    Summary for Aminoglycoside antibiotic
    Prescription only

    Gentamicin is a topical antibiotic that treats bacterial skin infections, such as impetigo. It comes as a cream that's useful for wet, oozing, or greasy skin infections. There's also a topical ointment for infections on dry skin. Both forms are applied on the skin 3 to 4 times a day. Gentamicin can be used on adults and children over 1 year of age. Most people don't have many side effects when used as directed. But it's possible to have mild skin irritation, like redness and itching.

    Summary for Nitroimidazole antibiotic
    Prescription only

    Metronidazole (Flagyl) is an oral antibiotic for adults and children. It's used to treat certain bacterial and parasitic infections, including bacterial vaginosis (a type of vaginal bacteria infection) and trichomoniasis (a sexually transmitted infection, or STI). Metronidazole (Flagyl) is taken by mouth, typically 3 times a day. Some common side effects of this medication include diarrhea, nausea, and vomiting. Avoid drinking alcohol while taking and for 3 days after stopping metronidazole (Flagyl) because this combination can cause a serious reaction. Metronidazole (Flagyl) is available as a lower-cost generic.

  • Indications of Gentamicin vs. Flagyl

    Indications for
    •Impetigo
    •Other bacterial skin infections
    Indications for

    Treatment of certain bacterial and parasitic infections, including:

    •Trichomoniasis
    •Amebiasis (parasitic gut infection)
    •Serious bacterial infections, such as:
    •Abdominal infection (including peritonitis)
    •Skin infections
    •Gynecological infections (including endometritis)
    •Bloodstream infection (septicemia)
    •Bone and joint infections
    •Central nervous system infections (meningitis)
    •Lung infections (lower respiratory tract infections)
    •Heart infection (endocarditis)

  • Pros and Cons of Gentamicin vs. Flagyl

    Pros and Const for Aminoglycoside antibiotic
    Pros
    •Treats various bacterial skin infections, including severe acne or impetigo
    •Very few side effects, so it's safe for most people if used as directed
    •Might be a good option for people who are sensitive to Neosporin
    Cons
    •Applied many times a day
    •Can cause temporary skin irritation
    •Need a prescription from a healthcare professional
    Pros and Const for Nitroimidazole antibiotic
    Pros
    •Taken by mouth
    •Available as a lower-cost generic medication
    •Can be used to treat different types of bacterial infection
    •Immediate-release formulations can be taken with or without food
    Cons
    •Immediate-release formulations needs to be taken multiple times a day for most infections
    •Serious interaction with alcohol
    •Can cause metallic taste in mouth
    •Not recommended while breastfeeding

  • Common Side Effects of Gentamicin vs. Flagyl

    Common Side Effects for
    •Side effects aren't common. See "Other Side Effects."
    Common Side Effects for

    Please note: These are common side effects reported by people who took extended-release metronidazole (Flagyl)

    •Headache (18%)
    •Inflammation of the vagina (15%)
    •Nausea (10%)
    •Metallic taste (9%)
    •Flu-like symptoms (6%)

  • Warnings of Gentamicin vs. Flagyl

    Common Side Effects for
    •Risk of other skin infections
    •Allergic reaction
    Common Side Effects for
    •Possible risk of cancer
    •Serious allergic reactions
    •Brain and nerve problems
    •Liver and kidney problems
    •Risk of fungal infection
    •Risk of drug resistance
    •Lower white blood cell counts
    •Interaction with other medications

  • Prices with our coupons for Gentamicin vs. Flagyl

    Learn more about Gentamicin
    Learn more about Metronidazole

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