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- What is rifaximin, and how does it work (mechanism of action)?
- What brand names are available for rifaximin?
- Is rifaximin available as a generic drug?
- Do I need a prescription for rifaximin?
- What are the side effects of rifaximin?
- What is the dosage for rifaximin?
- Which drugs or supplements interact with rifaximin?
- Is rifaximin safe to take if I'm pregnant or breastfeeding?
- What else should I know about rifaximin?
What is rifaximin, and how does it work (mechanism of action)?
Rifaximin is a semi-synthetic antibiotic used for treating traveler's diarrhea and hepatic encephalopathy. It is derived from rifamycin, a naturally occurring chemical produced by a bacterium called Streptomyces mediterranei. Rifaximin is active against Escherichia coli bacterial strains that cause traveler's diarrhea, preventing growth of the bacteria by preventing them from manufacturing proteins needed for their replication and survival. By suppressing growth of the bacteria, rifaximin reduces symptoms of traveler's diarrhea. Hepatic encephalopathy is a serious neurologic complication of advanced liver disease that affects the brain. It is believed to be caused by the absorption of ammonia and other chemicals produced by bacteria in the intestine. It is believed that rifaximin prevents and treats hepatic encephalopathy by reducing the intestinal bacteria that produce ammonia. The FDA approved rifaximin in May 2004.
What brand names are available for rifaximin?
Is rifaximin available as a generic drug?
GENERIC AVAILABLE: No
Do I need a prescription for rifaximin?
What are the side effects of rifaximin?
Common side effects associated with rifaximin include:
- urge to defecate,
- abdominal pain,
- flatulence, and
- fluid retention (edema).
Many of these side effects are also symptoms of traveler's diarrhea which rifaximin is used for treating. Rifaximin also causes allergic reactions, rash, and itching. Like other antibiotics rifaximin can alter the normal bacteria in the colon and encourage overgrowth of some bacteria such as Clostridium difficile which causes inflammation of the colon (pseudomembranous colitis). Patients who develop signs of pseudomembranous colitis after starting rifaximin (diarrhea, fever, abdominal pain, and possibly shock,) should contact their physician immediately.
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