Macrolides

What are macrolides?

Macrolides are a group (class) of antibiotics that treat bacterial infections. Macrolides work by preventing bacteria from growing. Like other antibiotics, macrolides won’t treat viral infections, such as the common cold or flu.

Your healthcare provider may prescribe a macrolide antibiotic if it’s the best medication to treat your specific type of infection. Macrolides are also an alternative if you’re allergic to other types of antibiotics, like penicillin.

Macrolide antibiotics list

The macrolides that U.S. healthcare providers most commonly prescribe are:

• Azithromycin
• Clarithromycin
• Erythromycin
• Fidaxomicin

Conditions that macrolides treat

Healthcare providers prescribe macrolides to treat a wide range of bacterial infections, including:

• Atypical pneumonia — commonly called “walking pneumonia”
• Bacterial eye infections
• C. diff infection
• Campylobacter infection
• Cat scratch fever
• Diphtheria
• H. pylori infection
• Legionnaires’ disease
• Nontuberculous mycobacteria (NTM) infections
• Sexually transmitted infections, like chlamydia
• Strep throat, typically in people with a penicillin allergy
• Traveler’s diarrhea, when severe
• Urethritis
• Whooping cough (pertussis)

Healthcare providers sometimes prescribe a macrolide (erythromycin in gel form) to treat acne. This is because bacteria living on your skin can clog your pores and contribute to acne breakouts. Applying erythromycin gel to your skin can help control surface bacteria.

In some cases, providers prescribe a macrolide along with other medications to treat a condition. For example, they use clarithromycin, another antibiotic and a proton pump inhibitor to treat ulcers due to H. Pylori infection.

How do I take a macrolide?

Macrolide antibiotics come in different forms, including:

• Pills you swallow
• Liquids you swallow
• Gels or solutions you apply to your skin
• Ointments you apply along your inner eyelid
• Injections your provider gives you

Follow the directions on the prescription label and ask your provider if you’re unsure how to take or use your medicine. When using a liquid form, always use the measuring device that comes with your medication. Don’t use a household spoon — it’s not an accurate way to measure medications.

How long will I need to take a macrolide antibiotic?

Your provider will tell you how many days you need to take your medication. The total course of your treatment depends on the specific type of infection you’re treating and your overall health. Take your medication for exactly as long as your provider says. If you stop too soon (even if you feel better), the antibiotic may not get rid of all the bacteria. This means the infection can come back stronger.

What are the potential benefits of macrolides?

Macrolide antibiotics successfully treat many different bacterial infections. They’re safe and effective for most people. Macrolides are also a helpful alternative if you have allergies to other antibiotics (like penicillin) for certain conditions.

What side effects do macrolides have?

Having an upset stomach is a common (and usually mild) side effect of macrolides and other antibiotics. You might experience:

• Nausea and vomiting
• Abdominal pain or cramping
• Diarrhea

Your risk of having an upset stomach varies according to the specific type of macrolide you’re taking. Some are more likely to upset your stomach than others. Your provider will tell you what to expect.

Macrolides may interact with other medications you’re taking. This means some of your medications might not work as well as they should. Tell your provider about all the medications and supplements you take. Also, tell them if you drink alcohol and how often you do. You might need to avoid alcohol while taking a macrolide. It can interact with medications and make antibiotics less effective.

Allergic reactions are rare but possible. A rash is the most common symptom.

Serious side effects are rare but can include Stevens-Johnson syndrome or its most severe form, toxic epidermal necrolysis.

Do macrolides cause arrhythmias?

Although it’s not common, macrolides may lead to abnormal heart rhythms (arrhythmias). This is because macrolides may prolong your heart’s QT interval. The QT interval is the time it takes your heart muscle to contract and then recover. When your QT interval is longer than normal, you’re at risk for a dangerous arrhythmia called Torsades de Pointes.

Your provider may recommend another type of antibiotic if you have long QT syndrome or other conditions that put you at risk for arrhythmias.

How long will it take for me to feel better?

It depends on the type of infection you have. Your provider will tell you what you can expect.

You may start feeling better before you’ve finished your antibiotics. But just because you feel better doesn’t mean the infection is fully cleared from your body. That’s why it’s important to take the full course of antibiotics as your provider prescribes. Doing so makes sure you get rid of the infection.

When should I call my healthcare provider?

Call your provider if you:

• Have questions about how to take your medication
• Have side effects that make it hard for you to take your medication (like nausea or vomiting)
• Still have symptoms after finishing your course of macrolides
• Develop a rash or other signs of an allergic reaction

Go to the emergency room if you:

• Have watery diarrhea multiple times in one day or signs of dehydration
• Have trouble breathing or other signs of anaphylaxis — this is a severe allergic reaction that needs immediate medical attention

Is clindamycin a macrolide?

No, clindamycin isn’t a macrolide. Clindamycin belongs to the lincosamides class of antibiotics. But clindamycin and macrolides work in similar ways to prevent bacteria growth.