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Compare Gentamicin vs. Polytrim

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

Key takeaways

Gentak (gentamicin) and Polytrim (polymyxin B/trimethoprim) are both prescription antibiotics used to treat bacterial eye infections, but they have some key differences. Gentak is an aminoglycoside antibiotic that works by blocking bacteria from making proteins needed for their protective covering, and it comes in both eye drop and ointment forms. Polytrim, on the other hand, is a combination of two antibiotics: polymyxin B, which breaks the bacteria's outer covering, and trimethoprim, which stops bacteria from making folic acid. Polytrim is only available as eye drops. Gentak is typically used every 4 hours or more frequently for severe infections, while Polytrim is used every 3 hours up to 6 times a day. Gentak can cause temporary eye irritation and blurry vision from the ointment, whereas Polytrim can cause eye irritation and increased sensitivity to light. Both medications are available in lower-cost generic forms and should be used exactly as prescribed to avoid new infections or resistance.

  • Gentamicin
    Polytrim (polymyxin B / trimethoprim)
  • Gentamicin
    Polytrim (polymyxin B / trimethoprim)

  • Summary of Gentamicin vs. Polytrim

    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 Antibiotic
    Prescription only

    Polytrim (polymyxin B / trimethoprim) is a combination antibiotic eye drop. It's used to treat mild-to-moderate bacterial eye infections, such as pink eye, in adults and children ages 2 months and older. The typical dose is 1 drop applied directly in the eye(s) every 3 hours for 7 to 10 days. Some of the more common side effects of this eye drop include symptoms of eye irritation, such as redness, stinging, and itching. Polytrim (polymyxin B / trimethoprim) is available as a lower-cost generic.

  • Indications of Gentamicin vs. Polytrim

    Indications for
    •Impetigo
    •Other bacterial skin infections
    Indications for
    •Mild-to-moderate infections on the eye and eyelid

  • Pros and Cons of Gentamicin vs. Polytrim

    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 Antibiotic
    Pros
    •Can treat a variety of eye infections in adults and children
    •Available as a lower-cost generic
    •Applied directly on the eyes, so it has less side effects than oral antibiotics
    Cons
    •Has to be used every 3 hours for at least a week
    •Can cause temporary eye irritation after applying
    •Can make your eyes more sensitive to light

  • Common Side Effects of Gentamicin vs. Polytrim

    Common Side Effects for
    •Side effects aren't common. See "Other Side Effects."
    Common Side Effects for
    •Eye irritation (e.g., redness, burning, stinging, itching)

  • Warnings of Gentamicin vs. Polytrim

    Common Side Effects for
    •Risk of other skin infections
    •Allergic reaction
    Common Side Effects for
    •For use in the eye only
    •New infection
    •Damage to contact lenses (when used in the eye)

  • Prices with our coupons for Gentamicin vs. Polytrim

    Learn more about Gentamicin
    Learn more about Polytrim

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