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Compare Erythromycin vs. Azithromycin

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

Key takeaways

Erythromycin (Ery-tab, E.E.S.) and azithromycin (Zithromax) are both macrolide antibiotics used to treat bacterial infections, such as respiratory and skin infections. They also share an off-label use for treating gastroparesis (slowed movement through the stomach and intestines). Both medications come as oral tablets and liquid forms and are available as lower-cost generics. However, they differ in several ways. Erythromycin is typically taken multiple times a day, while azithromycin is typically taken once daily. And you usually need to take azithromycin for a shorter amount of time. Erythromycin also seems more likely to cause stomach issues, such as nausea and diarrhea. Both medications can can cause QT prolongation, a heart rhythm problem, but this side effects is rare.

  • Erythromycin
    Azithromycin (Zithromax)
  • Erythromycin
    Azithromycin (Zithromax)

  • Summary of Erythromycin vs. Azithromycin

    Summary for Macrolide antibiotic
    Prescription only

    Erythromycin is an antibiotic that's used to treat a variety of infections caused by bacteria, including certain skin and respiratory infections. The dosage depends on the specific infection you're using it for. The most common side effects are related to the stomach, like nausea, vomiting, and diarrhea. Erythromycin comes in two forms that are taken by mouth: oral tablets and an oral suspension.

    Summary for Macrolide antibiotic
    Prescription only

    Azithromycin (Zithromax) is a macrolide antibiotic. It's used to treat many types of infections in children and adults, including strep throat, sinus infection, and pneumonia. Azithromycin (Zithromax) is taken by mouth once daily. Typically, the length of treatment ranges from 3 to 5 days, depending on the type of infection you have. For convenience, azithromycin (Zithromax) also comes pre-packaged as Z-Pak. Some of the more common side effects of azithromycin (Zithromax) include diarrhea, stomach pain, and nausea.

  • Indications of Erythromycin vs. Azithromycin

    Indications for
    •Respiratory infections (including upper respiratory tract infection and lower respiratory tract infection)
    •Listeria infection
    •Skin infections
    •Pertussis (whooping cough)
    •Diphtheria infection
    •Intestinal amebiasis
    •Sexually-transmitted infections, STIs (e.g., chlamydia, gonorrhea, syphilis)
    •Legionnaires’ Disease
    •Prevention of rheumatic fever
    Indications for

    Adults

    Azithromycin (Zithromax) can treat certain types of:

    •Sudden worsening of chronic obstructive pulmonary disease (COPD) from a bacterial infection
    •Bronchitis
    •Sinus infections
    •Pneumonia
    •Strep throat
    •Tonsil infections
    •Skin infections (e.g., cellulitis)
    •Urethra or cervix infections
    •Genital ulcer disease (chancroid)

    Children

    Azithromycin (Zithromax) can treat certain types of:

    •Ear infections (ages 6 months and older)
    •Pneumonia (ages 6 months and older)
    •Strep throat (ages 2 years and older)
    •Tonsil infections (ages 2 years and older)

  • Pros and Cons of Erythromycin vs. Azithromycin

    Pros and Const for Macrolide antibiotic
    Pros
    •Treats many types of infections
    •Available as a lower-cost generic
    •EES is available as an oral tablet or oral suspension
    Cons
    •Commonly causes nausea, diarrhea, vomiting, and stomach upset
    •Interacts with many medications
    •Has to be taken multiple times a day
    Pros and Const for Macrolide antibiotic
    Pros
    •Taken by mouth once daily
    •Treatment typically lasts only 3 to 5 days
    •Comes as a liquid; good option for people who've trouble swallowing tablets
    •Available as a lower-cost generic
    Cons
    •Might not be the best choice for people with severe liver problems or certain heart problems
    •Can cause stomach-related side effects, like diarrhea and stomach pain
    •Some bugs might be resistant to azithromycin (Zithromax)

  • Common Side Effects of Erythromycin vs. Azithromycin

    Common Side Effects for
    •Nausea
    •Vomiting
    •Stomach pain
    •Diarrhea
    •Anorexia
    Common Side Effects for

    Adults

    •Diarrhea (4-5%)
    •Nausea (3%)
    •Stomach pain (2-3%)

    Children

    •Diarrhea (2-6%)
    •Vomiting (1-6%)
    •Stomach pain (1-3%)

  • Warnings of Erythromycin vs. Azithromycin

    Common Side Effects for
    •Liver damage
    •Life-threatening changes in your heart rhythm (QT prolongation)
    •Syphilis in infants
    •Severe diarrhea
    •Interactions with other medications
    •Worsening of myasthenia gravis
    •Intestinal blockage in babies
    Common Side Effects for
    •Severe allergic and skin reactions
    •Liver damage
    •Heart rhythm problems (QT prolongation)
    •Possible higher risk of death from heart problems
    •Diarrhea from Clostridioides difficile infection
    •Worsening of certain muscle problems (myasthenia gravis)
    •Doesn't treat syphilis

  • Prices with our coupons for Erythromycin vs. Azithromycin

    Learn more about Erythromycin
    Learn more about Azithromycin

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