Xifaxan (rifaximin)  Coming Soon

Xifaxan (rifaximin) is an oral, minimally absorbed antibiotic approved by the FDA for three indications in adults: reducing the risk of hepatic encephalopathy recurrence, treating irritable bowel syndrome with diarrhea (IBS-D), and treating travelers diarrhea caused by noninvasive strains of Escherichia coli (in patients 12 years and older). It works locally in the gut with minimal absorption into the bloodstream. Xifaxan should not be used for diarrhea complicated by fever or blood in the stool, or diarrhea caused by pathogens other than E. coli.

In practice, no. Xifaxan is currently available only as a brand-name medication in the United States. A generic rifaximin has received FDA approval, but FDA approval does not mean a product is available in pharmacies, because active patents and ongoing patent litigation can legally prevent a generic from being sold. Based on the current patent situation, a generic rifaximin is generally not expected to be widely available until around 2029. This timeline is subject to change depending on litigation and patent activity. These dates are disclosed for general information and are not a guarantee.

QuickRx does not currently dispense Xifaxan (rifaximin). This page is provided for general educational information about the medication and its uses. If your situation changes or a generic rifaximin becomes available in the future, our dispensing options may change. For medications we do dispense, please see our other pages.

Irritable bowel syndrome with diarrhea (IBS-D) is a chronic functional gastrointestinal disorder marked by recurring abdominal pain, discomfort, bloating, and frequent loose or watery stools. Unlike inflammatory bowel disease, IBS-D does not cause visible damage to the intestines, but it can significantly affect quality of life. The exact cause is not fully understood but may involve gut-brain interactions, altered gut motility, intestinal bacteria, and heightened bowel sensitivity. Xifaxan (rifaximin) is an FDA-approved treatment for IBS-D in adults.

Hepatic encephalopathy is a decline in brain function that occurs when the liver cannot adequately remove toxins, particularly ammonia, from the blood. In patients with advanced liver disease or cirrhosis, these toxins can accumulate and affect brain function, causing symptoms that range from mild confusion and mood changes to severe disorientation. Triggers can include infections, dehydration, GI bleeding, and constipation. Xifaxan is FDA-approved to reduce the risk of hepatic encephalopathy recurrence in adults, typically used alongside lactulose therapy. Ongoing management by a hepatologist or gastroenterologist is important.

Travelers diarrhea is a common gastrointestinal illness that occurs when travelers, particularly those visiting developing regions, are exposed to unfamiliar bacteria, most often noninvasive strains of E. coli. It typically causes sudden loose stools, abdominal cramps, nausea, and sometimes vomiting. Xifaxan is FDA-approved for travelers diarrhea caused by noninvasive E. coli in adults and patients 12 years and older. It should not be used when diarrhea is complicated by fever or blood in the stool, and it is not effective against invasive pathogens such as Campylobacter, Shigella, or Salmonella. If symptoms do not improve within 24 to 48 hours, contact a healthcare provider.

Xifaxan can be taken with or without food, and the dose and duration depend on the condition being treated. For hepatic encephalopathy (prevention of recurrence), the labeled dose is 550 mg twice daily. For IBS-D, it is 550 mg three times daily for 14 days, and patients who experience a recurrence may be retreated with the same regimen up to two additional times. For travelers diarrhea, it is 200 mg three times daily for 3 days. Xifaxan comes in 200 mg and 550 mg tablets, so it is important the prescription matches the correct strength for the indication. Always follow your healthcare providers specific instructions.

Side effects can vary by indication and are generally reported more often in patients using Xifaxan for hepatic encephalopathy than for IBS-D or travelers diarrhea. Commonly reported effects in hepatic encephalopathy use include peripheral edema (swelling in the arms or legs), nausea, ascites (fluid buildup in the abdomen), dizziness, and fatigue. Other reported effects include muscle spasm, itching, abdominal pain, anemia, depression, nasopharyngitis, shortness of breath, fever, and joint pain. Headache is commonly reported in travelers diarrhea use. Talk with your healthcare provider about any side effects that concern you or do not go away.

Yes. Xifaxan carries important warnings to discuss with your prescriber. It works only in the gut and does not treat systemic infections or diarrhea caused by tissue-invasive bacteria, so diarrhea with fever or blood in the stool needs prompt medical attention and a different therapy. As with any antibiotic, Clostridioides difficile-associated diarrhea has been reported; contact a doctor for severe, persistent, or bloody diarrhea during or after treatment. Rare but serious skin reactions (including Stevens-Johnson syndrome and toxic epidermal necrolysis) and serious allergic reactions (including anaphylaxis and angioedema) have been reported; seek emergency care for blistering, peeling, severe rash, difficulty breathing, or swelling of the face or throat. Effectiveness for hepatic encephalopathy has not been established in patients with a MELD score greater than 25, and those with severe liver impairment (Child-Pugh C) should use it with caution.

Yes. Xifaxan has several clinically important drug interactions, so tell your healthcare provider and pharmacist about all medications, supplements, and herbal products you take. P-glycoprotein inhibitors (including certain HIV protease inhibitors and antifungals) may increase rifaximin levels. Rifaximin may reduce the anticoagulant effect of warfarin, so clotting levels should be monitored. Live oral vaccines such as cholera and typhoid (Ty21a) should be avoided during and within 14 days of antibiotic therapy. Concurrent antibiotic use may reduce the effectiveness of live fecal microbiota products. Rifaximin may reduce mycophenolate concentrations, and antibiotics including rifaximin may reduce the effectiveness of certain immune checkpoint inhibitor cancer therapies.

Xifaxan tablets should be stored at room temperature between 68°F and 77°F (20°C to 25°C), with brief excursions between 59°F and 86°F (15°C to 30°C) permitted. Keep the medication in its original container and out of reach of children. If you have questions about storing your medication, ask your pharmacist or prescriber.