What is Xifaxan?
Approved by the FDA for medical use in the United States in May 2004, Rifaximin, sold under the brand name Xifaxan among others, is an antibiotic that fights bacterial infection only in the intestines Rifaximin works differently from other antibiotics because it passes through your stomach and into your intestines without being absorbed into your blood stream. Because rifaximin treats only the intestinal tract, it will not treat infections of other parts of the body.
Xifaxan is used to treat travelers’ diarrhea caused by Escherichia coli (E. coli) in adults and children who are at least 12 years old. Travelers’ diarrhea (TD) is a stomach and intestinal infection. TD is defined as the passage of unformed stool (one or more by some definitions, three or more by others) while traveling. It may be accompanied by abdominal cramps, nausea, fever, and bloating. Occasionally bloody diarrhea may occur. Most people get this infection by eating food or drinking fluids that have been contaminated with the E. coli bacteria. Xifaxan is also used to treat irritable bowel syndrome (IBS) in adults whose main symptom is diarrhea.
Xifaxan is also used to lower the risk of a decline in brain function in adults with liver failure. Brain function can be affected when the liver stops working and cannot remove toxic substances from the body. SEE: How Fast Does Xifaxan Work
You should not use take Xifaxan if you are allergic to rifaximin or medications such as rifabutin (Mycobutin), rifampin (Rifater, Rifadin, Rifamate), or rifapentine (Priftin).
Before you take Xifaxan, tell your doctor if you have severe liver disease, diarrhea with fever, or diarrhea that is watery or has blood in it.
Take Xifaxan for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Rifaximin will not treat a viral infection such as the common cold or flu, or any form of diarrhea that is caused by a virus. Call your doctor if your symptoms do not improve after 24 hours, or if they get worse while taking this medicine. Xifaxan does not treat all bacterial forms of traveler’s diarrhea.
Before taking this medicine
You should not take Xifaxan if you are allergic to rifaximin, rifabutin, rifampin, or rifapentine.
To make sure Xifaxan is safe for you, tell your doctor if you have:
- liver disease;
- diarrhea with a fever; or
- watery or bloody diarrhea.
Tell your doctor if you are pregnant or breastfeeding.
Xifaxan should not be given to a child younger than 12 years old.
How should I take Xifaxan?
Take Xifaxan exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. You may take this medicine with or without food.
For travelers’ diarrhea, Xifaxan is usually taken for only 3 days. For IBS, it is usually taken for 2 weeks at a time. Follow your doctor’s dosing instructions very carefully.
Use this medicine for the full prescribed length of time, even if your symptoms quickly improve. Skipping doses can increase your risk of infection that is resistant to medication. Xifaxan will not treat a viral infection such as the flu or a common cold.
Do not share this medicine with another person, even if they have the same symptoms you have.
Call your doctor if your symptoms do not improve after 24 to 48 hours, or if they get worse while using this medicine.
Xifaxan does not treat all bacterial forms of travelers’ diarrhea.
Should be Given as Follows:
Adult: 200 mg orally every 8 hours for 3 days
Children under 12 years: Safety and efficacy not established
Children 12 years and older: 200 mg orally every 8 hours for 3 days, with or without food
Maintenance of remission
550 mg orally every 12 hours
Irritable Bowel Syndrome
Indicated for irritable bowel syndrome with diarrhea (IBS-D) in adult men and women
550 mg orally every 8 hours for 14 days; recurrence of symptoms can be retreated with a 14 day treatment course, up to 2 times
Available in unit-dose package containing 42 tablets (i.e., 2 week supply) for this indication
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What happens if I miss a dose?
Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.
What should I avoid while taking Xifaxan?
Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, call your doctor before using anti-diarrhea medicine.
Xifaxan side effects
Get emergency medical help if you have signs of an allergic reaction to Xifaxan: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have:
- severe stomach pain, diarrhea that is watery or bloody (even if it occurs months after your last dose);
- fever; or
- fluid build-up around the stomach – rapid weight gain, stomach pain and bloating, trouble breathing while lying down.
Common Xifaxan side effects may include:
- swelling in your hands or feet;
- headache, dizziness;
- tiredness; or
- abnormal liver function tests.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. SEE: Does Xifaxan Kill Candida?
What other drugs will affect Xifaxan?
Tell your doctor about all your other medicines, especially:
- warfarin (Coumadin, Jantoven);
- an antibiotic – clarithromycin, erythromycin;
- antiviral medicine – ritonavir, saquinavir; or
- heart or blood pressure medicine – amiodarone, quinidine, verapamil.
This list is not complete. Other drugs may interact with rifaximin, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.