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Compare Unasyn vs. Augmentin

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

Key takeaways

Unasyn (ampicillin/sulbactam) and Augmentin (amoxicillin/clavulanate) are both combination antibiotics that belong to the penicillin class and include a beta-lactamase inhibitor. They are used to treat various bacterial infections, including skin infections, but they differ in several ways. Unasyn is administered as an injection (IV or IM) and is typically used in a healthcare setting, while Augmentin is taken orally as tablets, chewable tablets, or a liquid suspension. Unasyn is not FDA-approved for urinary tract infections (UTIs), whereas Augmentin is approved for this use. Unasyn is given four times daily, while Augmentin is usually taken two to three times daily. Both medications are available as lower-cost generics. Common side effects of Unasyn include pain at the injection site, diarrhea and rash, while Augmentin commonly causes diarrhea, nausea, and rash. Both medications can cause serious allergic reactions, especially if you have a penicillin allergy, and they can interact with other medications, so it's important to inform your healthcare team about all the medications you are taking.

  • Unasyn (ampicillin / sulbactam)
    Augmentin (amoxicillin / clavulanate)
  • Unasyn (ampicillin / sulbactam)
    Augmentin (amoxicillin / clavulanate)

  • Summary of Unasyn vs. Augmentin

    Summary for Penicillin antibiotic / Beta-lactamase inhibitor
    Prescription only

    Unasyn (ampicillin / sulbactam) is a combination medication that contains a penicillin and beta-lactamase inhibitor. This antibiotic is used to treat several types of infections throughout the body in adults and children. Doses are given as injections into the vein (IV) or muscle (IM) every 6 hours. Unasyn (ampicillin / sulbactam) is available as a brand-name medication and lower-cost generic. Side effects aren't common, but can include pain at the injection site and diarrhea.

    Summary for Penicillin antibiotic / Beta-lactamase inhibitor
    Prescription only

    Augmentin (amoxicillin / clavulanate) is an antibiotic medication. It contains a penicillin and a beta-lactamase inhibitor. This antibiotic treats many types of bacterial infections, like urinary tract infection (UTI), sinus infection, and ear infection, among others. It fights infections by preventing bacteria from protecting themselves from harm. This medication comes as tablets, chewable tablets, and a suspension that are taken by mouth typically two to three times daily. It's approved for use in adults and children. Common side effects include diarrhea, nausea, and rash.

  • Indications of Unasyn vs. Augmentin

    Indications for
    •Skin infections (e.g., cellulitis)
    •Stomach infections
    •Gynecological infections (e.g., vaginal, cervical, pelvic inflammatory disease)
    Indications for
    •Ear infections
    •Sinus infections
    •Lower respiratory tract infections
    •Skin infections (e.g., cellulitis)
    •Urinary tract infections (UTIs)

  • Pros and Cons of Unasyn vs. Augmentin

    Pros and Const for Penicillin antibiotic / Beta-lactamase inhibitor
    Pros
    •Treats many types of bacterial infections
    •Can use for fighting bacterial infections in children as young as 1 year of age
    •Available as a lower-cost generic
    Cons
    •Typically needs to be given every 6 hours
    •Must be given as an IV or IM injection by a healthcare professional
    •Might not be a safe choice if you've had a severe allergy to penicillins
    Pros and Const for Penicillin antibiotic / Beta-lactamase inhibitor
    Pros
    •Treats many types of bacterial infections in children and adults
    •Available as a tablet, chewable tablet, and oral suspension
    •Available as a lower-cost generic
    •Safe to use while pregnant and while breastfeeding
    Cons
    •Typically need to take 2 or 3 times daily
    •Might not be able to take this antibiotic if you've had a severe penicillin allergy
    •Can cause stomach side effects like nausea, vomiting, and diarrhea

  • Common Side Effects of Unasyn vs. Augmentin

    Common Side Effects for
    •Pain at injection site (16% for IM injections, 3% for IV injections)
    •Diarrhea (3%)
    •Rash (up to 2%)
    Common Side Effects for

    Immediate-release tablets, chewable tablets, and suspension

    •Diarrhea or loose stools (9%)
    •Nausea (3%)
    •Skin rash (3%)

    Extended-release tablets

    •Diarrhea (15%)
    •Vaginal yeast infection (3%)

    Augmentin ES-600 (amoxicillin / clavulanate) suspension

    •Vomiting (7%)
    •Fever (6%)
    •Rash (6%)
    •Upper respiratory tract infection (e.g., common cold; 4%)
    •Diarrhea (4%)

  • Warnings of Unasyn vs. Augmentin

    Common Side Effects for
    •Allergic reactions
    •Severe skin reactions
    •Liver problems
    •Diarrhea from Clostridioides difficile infection
    Common Side Effects for
    •Severe allergic reactions and skin reactions
    •Liver problems
    •Diarrhea from Clostridioides difficile infection
    •Caution use in people with phenylketonuria (PKU) - for chewable tablets and suspension

  • Prices with our coupons for Unasyn vs. Augmentin

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