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    Antibiotics for Pneumonia



    Generic Name Brand Name
    azithromycin Zithromax, Zmax
    clarithromycin Biaxin
    erythromycin Eryc, EryPed, Ery-Tab


    Generic Name Brand Name
    doxycycline Doryx, Vibramycin


    Generic Name Brand Name
    gemifloxacin Factive
    levofloxacin Levaquin
    moxifloxacin Avelox


    Generic Name Brand Name
    cefuroxime Ceftin
    cephalexin Keflex


    Generic Name Brand Name
    amoxicillin with clavulanate Augmentin
    ticarcillin with clavulanate Timentin


    Generic Name Brand Name
    vancomycin Vancocin

    How It Works

    Antibiotics kill bacteria or prevent them from reproducing.

    Why It Is Used

    Doctors use antibiotics to treat pneumonia caused by bacteria. There are many types of antibiotics. Your doctor will decide which antibiotic will work best for you.

    Doctors do not use tetracyclines for children younger than age 8. These medicines can discolor a child's teeth.

    Doctors use vancomycin to treat people who are in the hospital for severe infections that do not respond to other antibiotics.

    How Well It Works

    In general, all antibiotics used have a high cure rate for pneumonia caused by bacteria. Cure rates are greater than 80%, meaning at least 80 people out of 100 are cured.1

    Vancomycin works against some types of bacteria that have become resistant to other antibiotics.

    You most likely will have some improvement in symptoms 2 to 3 days after treatment begins. Unless you get worse during that time, treatment is not changed for at least 3 days. The number of days you keep taking antibiotics depends on your illness and the type of antibiotic.

    Side Effects

    All medicines have side effects. But many people don't feel the side effects, or they are able to deal with them. Ask your pharmacist about the side effects of each medicine you take. Side effects are also listed in the information that comes with your medicine.

    Here are some important things to think about:

    • Usually the benefits of the medicine are more important than any minor side effects.
    • Side effects may go away after you take the medicine for a while.
    • If side effects still bother you and you wonder if you should keep taking the medicine, call your doctor. He or she may be able to lower your dose or change your medicine. Do not suddenly quit taking your medicine unless your doctor tells you to.

    Call911or other emergency services right away if you have:

    Call your doctor right away if you have:

    • Hives.
    • Sudden pain or swelling around your ankle, shoulder, elbow, or hand. Some antibiotics increase the risk of a tendon rupture or other tendon damage. Do not exercise until your doctor says it is okay.

    Common side effects of this medicine include:

    Some fluoroquinolones and tetracyclines may make it easier to get a sunburn when you are taking them. Avoid direct sunlight and tanning salons while you are taking these medicines and for 5 days after you have stopped taking them.

    • Most sunscreens do not block enough of the UV rays to prevent sunburn.
    • If you cannot avoid direct sunlight, cover as much of your body as you can with clothing.

    A large study showed that people who take erythromycin along with certain common medicines have an increased risk of sudden cardiac death.2 The study showed that the risk of sudden cardiac death is greater when erythromycin is taken with some medicines that inhibit certain liver enzymes-such as some calcium channel blockers, some antifungal medicines, medicines to stop vomiting, and some antidepressants-than when erythromycin is taken by itself.

    Vancomycin can cause hearing loss. This is rare. But it has occurred in people who received excessive doses or who have kidney disease. Hearing loss also has occurred in people who were taking another medicine that may cause hearing loss or who already had some hearing loss.

    See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

    What To Think About

    Antibiotics cannot always kill bacteria (antibiotic resistance), in part because they are used too much or are used incorrectly. You can help prevent antibiotic resistance by taking all of your medicine as directed, even if you feel better after a few days. If you stop taking your medicine too soon, bacteria that are not killed in the first few days of treatment can grow stronger and become resistant to the antibiotic.

    Doctors are careful about the use of vancomycin, because it is the only antibiotic that can kill some types of bacteria. Using vancomycin too often can lead to antibiotic resistance in these bacteria.

    Taking medicine

    Medicine is one of the many tools your doctor has to treat a health problem. Taking medicine as your doctor suggests will improve your health and may prevent future problems. If you don't take your medicines properly, you may be putting your health (and perhaps your life) at risk.

    There are many reasons why people have trouble taking their medicine. But in most cases, there is something you can do. For suggestions on how to work around common problems, see the topic Taking Medicines as Prescribed.

    Advice for women

    If you are pregnant, breast-feeding, or planning to get pregnant, do not use any medicines unless your doctor tells you to. Some medicines can harm your baby. This includes prescription and over-the-counter medicines, vitamins, herbs, and supplements. And make sure that all your doctors know that you are pregnant, breast-feeding, or planning to get pregnant.


    Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

    Complete the new medication information form (PDF)(What is a PDF document?) to help you understand this medication.


    1. Loeb M (2010). Community-acquired pneumonia, search date January 2010. Online version of BMJ Clinical Evidence:

    2. Ray WA, et al. (2004). Oral erythromycin and the risk of sudden death from cardiac causes. New England Journal of Medicine, 351(11): 1089-1096.

    ByHealthwise Staff
    Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
    Specialist Medical ReviewerR. Steven Tharratt, MD, MPVM, FACP, FCCP - Pulmonology, Critical Care Medicine, Medical Toxicology

    Current as ofSeptember 9, 2014

    WebMD Medical Reference from Healthwise

    Last Updated: September 09, 2014
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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