Key takeaways
- Xifaxan (rifaximin) is a brand-name drug prescribed for irritable bowel syndrome with diarrhea (IBS-D), traveler’s diarrhea, and hepatic encephalopathy (HE). The drug’s dosage varies depending on a person’s age and the condition being treated.
- Xifaxan comes as an oral tablet that’s typically taken 2 to 3 times per day. It can be taken with or without food.
- While Xifaxan may be prescribed off-label for conditions such as small intestinal bacterial overgrowth (SIBO), it’s important to consult your doctor to determine the right dosage for you.
Xifaxan’s active ingredient is rifaximin, an antibiotic. This medication is unavailable in a generic version.
Keep reading for specific information about Xifaxan dosages, including its strengths and how to take the medication.
The following information describes dosages that are commonly prescribed or recommended in adults. However, be sure to take the dosage your doctor prescribes. Your doctor will determine the best dosage to fit your needs.
Xifaxan form
Xifaxan comes as an oral tablet.
Xifaxan strengths
Xifaxan tablets come in two strengths: 200 milligrams (mg) and 550 mg.
The typical dosage of Xifaxan for irritable bowel syndrome with diarrhea (IBS-D) in adults is 550 mg three times per day for 14 days. If your diarrhea comes back, your doctor may prescribe the same dosage regimen up to two more times.
The typical dosage of Xifaxan for traveler’s diarrhea in adults is 200 mg three times per day for 3 days.
The typical dosage of Xifaxan for hepatic encephalopathy (HE) in adults is 550 mg two times per day. You’ll take this dosage long term as long as your doctor recommends it.
Note: Xifaxan is used to help prevent repeat episodes of overt HE due to liver cirrhosis. “Overt” means the symptoms are noticeable and severe.
Xifaxan is used to treat traveler’s diarrhea in children ages 12 years and older. The typical dosage is the same as the adult dosage: 200 mg three times per day for 3 days.
Below are some frequently asked questions about Xifaxan’s dosage.
Do I need to take my Xifaxan dose before or after food?
You can take your Xifaxan dose before or after food. Xifaxan comes as a tablet you swallow with or without food. Always follow your doctor’s directions for taking the drug. For more details, refer to the “How to take Xifaxan” section.
If you have more questions about how to take Xifaxan, talk with your doctor or pharmacist.
Can Xifaxan be used for SIBO or liver cirrhosis? If so, what is the dosage?
Xifaxan may be used off label for small intestinal bacterial overgrowth (SIBO). With off-label use, a drug is prescribed for a purpose other than what it’s approved for.
With SIBO, excess levels of bacteria grow in your small intestine. The symptoms can include bloating, diarrhea, and constipation. If you’re interested in Xifaxan for SIBO, talk with your doctor. If they prescribe the drug, they’ll determine the right dosage for you.
Xifaxan is approved to help prevent repeat episodes of overt HE due to liver cirrhosis. (“Overt” means the condition causes noticeable and severe symptoms.) To determine the typical dosage for HE, see the “Dosage of Xifaxan for HE” section.
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Xifaxan comes as a tablet you swallow, with or without food. The drug manufacturer doesn’t say whether to crush, chew, or split the tablets.
If you have trouble swallowing tablets, talk with your doctor or pharmacist for tips on how to take this form of medication.
How long do you take Xifaxan?
For IBS-D and traveler’s diarrhea, Xifaxan isn’t meant to be taken long term. If your doctor prescribes Xifaxan for these conditions, you’ll typically take the drug for 3 to 14 days.
If your doctor prescribes Xifaxan for HE, you’ll likely take it for as long as they recommend.
ACCESSIBLE DRUG LABELS AND CONTAINERSSome pharmacies offer labels with large print, braille, or a code you scan with a smartphone to convert text to speech. If your local pharmacy doesn’t have these options, your doctor or pharmacist might be able to recommend a pharmacy that does.
If you’re having trouble opening medication bottles, ask your pharmacist about putting Xifaxan in an easy-open container. They also may recommend tools that can make it easier to open bottles.
The drug manufacturer doesn’t provide guidance on missed doses. If you miss a dose of Xifaxan, ask your doctor or pharmacist what they recommend.
To help make sure that you don’t miss a dose, try using a medication reminder. This can include setting an alarm or putting a note where you’ll see it, such as on your bathroom mirror or bedside table. You could also download a reminder app on your phone.
It’s important that you do not take more Xifaxan than your doctor prescribes. For some medications, taking more than the recommended amount may lead to harmful effects or overdose.
Call your doctor right away if you believe you’ve taken too much Xifaxan. They’ll likely stop Xifaxan treatment and treat any side effects you may have.
Another option is to call America’s Poison Centers at 800-222-1222 or use its online tool. If you have severe symptoms, immediately call 911 or your local emergency number, or go to the nearest emergency room.
Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.
