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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

Rifamycins are antibiotics that work by suppressing the bacteria's production of genetic material. As a result, the bacteria die.

Rifamycins include the following:

Rifampin, rifabutin, and rifapentine are used in combination with other antibiotics to treat tuberculosis and infections related to tuberculosis. They have similar side effects.

Rifampin is often used in combination with other antibiotics to treat leprosy and artificial valves and joints infected with staphylococci.

Rifaximin is used to treat traveler's diarrhea caused by Escherichia coli (E. coli).



Common Uses

Some Side Effects




Tuberculosis and infections related to tuberculosis

For rifampin: Leprosy


Liver dysfunction

Gastrointestinal upset

Red-orange saliva, sweat, tears, and urine

Interactions with many drugs, often requiring changes in the dose


Traveler’s diarrhea

Nausea, vomiting, abdominal pain, and flatulence

(See also Overview of Antibiotics.)

Use of Rifamycins During Pregnancy and Breastfeeding

Rifamycins are used during pregnancy only when the benefits of treatment outweigh the risks. With rifabutin, no harmful effects on the fetus have been observed in animal studies, but no well-designed studies have been done in pregnant women. With rifampin and rifapentine, harmful effects on the fetus (including birth defects) have been observed in animal studies. (See also Drug Use During Pregnancy.)

Use of rifamycins during breastfeeding is not recommended. A decision to stop breastfeeding or to stop rifampin should be made depending on the importance of the drug to the mother's health. (See also Drug Use During Breastfeeding.)

Drugs Mentioned In This Article

Generic Name Select Brand Names
Rifapentine PRIFTIN
Rifaximin XIFAXAN

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