Macrolides

ByBrian J. Werth, PharmD, University of Washington School of Pharmacy
Reviewed/Revised May 2024
VIEW PROFESSIONAL VERSION

Macrolides are a class of antibiotics that are often used to treat infections in people who are allergic to penicillins.

Macrolides include the following:

Macrolides work by preventing bacteria from producing proteins they need to grow and multiply.

absorbed into the bloodstream when taken orally. It is used to treat Clostridioides difficileinduced colitis but does not do much harm to the other bacteria that normally live in healthy intestines.

Macrolides interact with many other medications (called a drug-drug interaction). Often, the interaction increases the effects, including the side effects, of the other medications. When given with certain other medications, macrolides can increase the risk of sudden cardiac death in people who have long QT syndrome.

Table

(See also Overview of Antibiotics.)

Use of Macrolides During Pregnancy and Breastfeeding

Macrolides should be taken during pregnancy only when the benefits of treatment outweigh the risks.

Erythromycin is considered among the safest antibiotics to use during pregnancy. It is considered safer than azithromycin because it has been used more, and thus more is known about it.

clarithromycin except when there is no alternative medication. (See also Safety of Medications During Pregnancy.)

Use of erythromycin during breastfeeding is generally considered acceptable. Whether other macrolides are safe to use during breastfeeding is unknown. (See also Medication and Substance Use During Breastfeeding.)

Drugs Mentioned In This Article
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