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Brian J. Werth

, PharmD, University of Washington School of Pharmacy

Last full review/revision Jul 2020| Content last modified Jul 2020

Carbapenems are a subclass of antibiotics called beta-lactam antibiotics (antibiotics that have a chemical structure called a beta-lactam ring). Beta-lactam antibiotics also include cephalosporins, monobactams, and penicillins.

Carbapenems are broad-spectrum antibiotics. That is, they are effective against many types of bacteria, including bacteria that are resistant to many other antibiotics.

Carbapenems include the following:

Carbapenems must be given by injection. They are often used with aminoglycosides to treat some infections because using them together enhances the effectiveness of both antibiotics.

Imipenem is always given in combination with other drugs cilastatin and sometimes also relebactam. Cilastatin and relebactam are not antibiotics. They help prolong the effect of imipenem by protecting it from being broken down.

Some bacteria have an outer covering (cell wall) that protects them. Like other beta-lactam antibiotics, carbapenems work by preventing bacteria from forming this cell wall, resulting in death of the bacteria.

Rarely, because carbapenems are structurally similar to the penicillins, people who have an allergic reaction to penicillins have an allergic reaction to carbapenems.



Common Uses

Some Side Effects










Abdominal and urinary infections

Infections due to susceptible bacteria resistant to other antibiotics

Except for ertapenem, Pseudomonas infections or enterococcal infections

Uncommonly, seizures (risk is slightly higher with imipenem)


Rarely, an allergic reaction in people who are allergic to penicillin

(See also Overview of Antibiotics.)

Use of Carbapenems During Pregnancy and Breastfeeding

When carbapenems were given to pregnant animals, no harmful effects on the fetus were observed. However, carbapenems have not been tested in pregnant women. (See also Drug Use During Pregnancy.)

Carbapenems are excreted in breast milk and may affect the balance of normal bacteria in the baby's digestive tract. (See also Drug Use During Breastfeeding.)

Drugs Mentioned In This Article

Generic Name Select Brand Names
Doripenem DORIBAX
Meropenem MERREM
Ertapenem INVANZ

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