Uses

What is Xifaxan used for?

Xifaxan (rifaximin) is commonly used for the following conditions.

  • Treatment of travelers’ diarrhea (TD), an intestinal infection caused by eating or drinking contaminated food or water. Xifaxan may not be appropriate for some travelers’ diarrhea infections, depending on which germs are causing the infection. Bacteria in some locations may have developed resistance to Xifaxan, which will make it not work as well. 
  • Treatment of irritable bowel syndrome with diarrhea (IBS-D)
  • To lower the risk of hepatic encephalopathy, a brain condition caused by severe liver disease

Xifaxan may also be used for other conditions as determined by your healthcare provider.

How does Xifaxan work (mechanism of action)?

Xifaxan kills certain types of bacteria by blocking proteins they need to grow and multiply. These bacteria can cause traveler’s diarrhea but may also contribute to hepatic encephalopathy and irritable bowel syndrome with diarrhea (IBS-D). 

How is Xifaxan supplied (dosage forms)?

Brands and other names

  • Xifaxan

Dosage forms and strengths

  • 200 mg, 550 mg oral tablets 

How should I store Xifaxan?

Xifaxan should be stored at room temperature, between 68 F to 77 F (20 C to 25 C). It can be exposed to temperatures between 59 F to 86 F (15 C to 30 C), for shorter periods of time, such as when transporting it. Store in a cool, dry place.

Side Effects

What are the most common side effects of Xifaxan?

The most common side effects of Xifaxan are listed below. The frequency of these side effects can vary based on the reason you are taking the medicine. Tell your healthcare provider if you have any of these side effects that bother you.

There may be other side effects of Xifaxan that are not listed here. Contact your healthcare provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of Xifaxan?

While less common, the most serious side effects of Xifaxan are described below, along with what to do if they happen.

Antibiotic-Associated Diarrhea. An overgrowth of germs called Clostridioides difficile, or “C. diff,” may happen in your gut with many types of antibiotics, including Xifaxan. This can cause a condition known as antibiotic-associated diarrhea and can happen even up to two months after stopping the antibiotic. Call your healthcare provider right away if you have any of the following symptoms of this condition.

  • Watery diarrhea
  • Diarrhea that does not go away
  • Blood in your stool (poop)
  • Severe stomach cramps
  • Fever that starts after you start or finish the medicine

Warnings & Precautions

Who should not use Xifaxan?

Allergies to Ingredients. People who are allergic to any of the following should not take Xifaxan.

  • Xifaxan 
  • Rifaximin
  • Any other medicine known as a rifamycin antimicrobial agent or rifaximin antibiotic
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in Xifaxan.

What should I know about Xifaxan before using it?

Do not take Xifaxan unless it has been prescribed to you by a healthcare provider. Take it as prescribed.

Do not share Xifaxan with other people, even if they have the same condition as you. It may harm them.

Keep Xifaxan out of the reach of children.

Xifaxan is not used to treat viral infections, such as the common cold, flu, or diarrhea caused by a virus.

If you are taking Xifaxan for travelers’ diarrhea, stop Xifaxan and talk to your healthcare provider if diarrhea is still happening 24 to 48 hours after you started taking Xifaxan or if your diarrhea gets worse. 

What should I tell my healthcare provider before using Xifaxan?

Tell your healthcare provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if Xifaxan is right for you.

In particular, make sure that you discuss any of the following.

Current and Past Health Conditions. Tell your healthcare provider if you have any of the following health conditions.

  • Liver disease
  • Diarrhea with fever 
  • Blood in the stool

Other Medicines and Supplements. Xifaxan may interact with other medicines and supplements. Before taking Xifaxan, tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. It is not known if or how Xifaxan could affect pregnancy or harm an unborn baby. Tell your healthcare provider if you are or plan to become pregnant. 

Breastfeeding. It is not known if Xifaxan passes into breast milk. Tell your healthcare provider if you are breastfeeding or plan to breastfeed. Your healthcare provider will advise you if you should take Xifaxan while breastfeeding.

How can I get more information about Xifaxan?

For more information about Xifaxan, you can visit the manufacturer’s website at www.xifaxan.com or call them at 800-321-4576.

Interactions

Does Xifaxan interact with foods or drinks?

There are no known interactions between Xifaxan and foods or drinks.

It is unknown if drinking alcohol will affect Xifaxan. The risk of dizziness or tiredness may be increased if you drink alcohol while taking Xifaxan. Heavy drinking can slow your immune response and make it harder for your body to fight infection. 

Does Xifaxan interact with other medicines (drug interactions)?

Always tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are using any of the following before taking Xifaxan.

  • Cyclosporine (Gengraf, Neoral, Sandimmune, and others), which is a medicine to suppress your immune system
  • Warfarin, which is a blood thinner
  • Verapamil (Verelan, Verelan PM), which is a medicine used for high blood pressure or chest pain

Some other medicines may alter the blood levels of Xifaxan. Tell your healthcare provider about all medicines that you take or have recently taken.

This may not be a complete list of medicines that can interact with Xifaxan. Always check with your healthcare provider.

Does Xifaxan (rifaximin) interact with other drugs you are taking?
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Overdose/Missed Dose

What should I do if I accidentally use too much Xifaxan?

If you or someone else has taken too much Xifaxan, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of Xifaxan?

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and only take the next dose. Do not take double or extra doses.

It is important to complete your prescribed course of Xifaxan, even if your symptoms get better or go away. This will reduce the risk that future infections are not resistant to Xifaxan or other similar medicines.

Drug Survey

Are you currently using Xifaxan (rifaximin)?

This survey is being conducted by the WebMD marketing sciences department.