Xifaxan (rifaximin) is a prescription oral tablet that’s used to help prevent episodes of hepatic encephalopathy and to treat diarrhea from certain causes. This drug can interact with other medications. For example, Xifaxan can interact with cyclosporine and warfarin.
Xifaxan is prescribed to help:
- decrease the recurrence of overt (obvious) episodes of hepatic encephalopathy in adults
- treat traveler’s diarrhea caused by Escherichia coli (E. coli) bacterium* in adults and some children
- treat irritable bowel syndrome with diarrhea (IBS-D) in adults
Xifaxan contains the active ingredient rifaximin. (An active ingredient is what makes a drug work.)
An interaction can occur because one substance causes another substance to have a different effect than expected. Interactions can also occur if you have certain health conditions.
Keep reading to learn about Xifaxan’s possible interactions. And for more information about Xifaxan, including details about its uses, see this in-depth article.
Before you start taking Xifaxan, tell your doctor and pharmacist about any prescription, over-the-counter, or other drugs you take. Sharing this information with them may help prevent possible interactions. (To learn whether Xifaxan interacts with supplements, herbs, and vitamins, see the “Are there other interactions with Xifaxan?” section below.)
If you have questions about drug interactions that may affect you, talk with your doctor or pharmacist.
The table below lists drugs that may interact with Xifaxan. Keep in mind that this table does not include all drugs that may interact with Xifaxan. For more information about some of these interactions, see the “Drug interactions explained” section below.
| Drug group or drug name | Drug examples | What can happen |
| certain drugs for abnormal heart rhythm | • amiodarone (Pacerone) • propafenone (Rythmol SR) | can increase the risk of side effects of Xifaxan |
| certain antibiotics called macrolides | • erythromycin (Eryc, others) • clarithromycin | can increase the risk of side effects of Xifaxan |
| certain antifungals | • ketoconazole • itraconazole (Sporanox, Tolsura) | can increase the risk of side effects of Xifaxan |
| certain drugs for treating hepatitis C | • sofosbuvir/velpatasvir (Epclusa) • glecaprevir/pibrentasvir (Mavyret) | can increase the risk of side effects of Xifaxan |
| certain drugs for treating HIV | • cobicistat (Tybost) • ritonavir (Norvir) | can increase the risk of side effects of Xifaxan |
| cyclosporine (Gengraf, Neoral, Sandimmune) | — | can increase the risk of side effects of Xifaxan |
| ranolazine (Ranexa) | — | can increase the risk of side effects of Xifaxan |
| verapamil (Verelan) | — | can increase the risk of side effects of Xifaxan |
| warfarin (Jantoven) | can make warfarin less effective |
Certain health conditions or other factors could raise your risk of harm if you take Xifaxan. In such cases, your doctor may not prescribe Xifaxan for you. These are known as contraindications. A contraindication to taking Xifaxan is a past allergic reaction.
If you’ve had an allergic reaction to Xifaxan or any of its ingredients, your doctor likely won’t prescribe Xifaxan. This is because taking the drug could cause another allergic reaction. You can ask your doctor about other treatments that may be better options for you.
Xifaxan is not known to interact with alcohol. But Xifaxan and alcohol can cause some similar side effects, such as headache and nausea. So you may be more likely to experience these side effects if you drink alcohol during your Xifaxan treatment.
If you’re taking Xifaxan to treat hepatic encephalopathy, your doctor will likely recommend avoiding alcohol. This is because consuming alcohol can trigger an episode of hepatic encephalopathy in people with severe liver disease.
If you have questions about consuming alcohol during Xifaxan treatment, talk with your doctor or pharmacist.
Learn more about certain drug interactions that can occur with Xifaxan.
Interaction with certain antibiotics
Xifaxan can interact with certain antibiotics, which are prescribed to treat infections caused by bacteria.
Examples of antibiotic medications that interact with Xifaxan include:
- clarithromycin
- erythromycin (Eryc, Ery-Tab)
What could happen
Some antibiotics decrease the activity of a protein called P-glycoprotein (P-gp). This protein helps remove certain drugs from your body, including Xifaxan. If you’re taking Xifaxan with one of these antibiotics, Xifaxan can build up in your body. This raises your risk of side effects from Xifaxan.
What you can do
If you take Xifaxan with an antibiotic that affects P-gp, your doctor will likely advise you to watch closely for side effects. If you’ll be taking both medications long term, they may prescribe a lower dose of one or both drugs.
If you have questions about taking Xifaxan with antibiotics, talk with your doctor or pharmacist.
Interaction with certain drugs for treating hepatitis C
Xifaxan can interact with certain medications prescribed to treat hepatitis C.
Examples of medications prescribed to treat hepatitis C that interact with Xifaxan include:
- glecaprevir/pibrentasvir (Mavyret)
- ledipasvir/sofosbuvir (Harvoni)
- sofosbuvir/velpatasvir/voxilaprevir (Vosevi)
- sofosbuvir/velpatasvir (Epclusa)
What could happen
These drugs decrease the activity of P-gp. This protein helps remove Xifaxan from your body. If you’re taking Xifaxan with one of these hepatitis C treatments, Xifaxan could build up in your body. This can increase your risk of side effects from Xifaxan.
What you can do
If you’re prescribed Xifaxan and a hepatitis C medication that affects P-gp, your doctor will monitor you closely for Xifaxan side effects. They may prescribe a lower Xifaxan dosage for you, especially if you develop side effects after taking these drugs together.
Interaction with certain drugs for treating HIV
Xifaxan can interact with certain drugs prescribed to treat HIV.
Examples of drugs that treat HIV and interact with Xifaxan include:
- cobicistat (Tybost) and drugs that contain cobicistat, such as cobicistat/elvitegravir/emtricitabine/tenofovir disoproxil fumarate (Stribild)
- ritonavir (Norvir) and drugs that contain ritonavir, such as Kaletra (lopinavir/ritonavir)
What could happen
These drugs decrease the activity of P-gp. This protein helps remove Xifaxan from your body. If you’re taking Xifaxan with one of these HIV treatments, Xifaxan could build up in your body. This can increase your risk of side effects from Xifaxan.
What you can do
If you’re prescribed both Xifaxan and an HIV treatment that affects P-gp, your doctor will monitor you closely for side effects from Xifaxan. Or your doctor may suggest alternative treatments that don’t interact.
Xifaxan may have other interactions. They could occur with supplements, foods, vaccines, or even lab tests. See below for details. Note that the information below does not include all other possible interactions with Xifaxan.
Does Xifaxan interact with supplements?
Before you start taking Xifaxan, talk with your doctor and pharmacist about any supplements, herbs, and vitamins you take. Sharing this information with them may help you avoid possible interactions.
If you have questions about interactions that may affect you, talk with your doctor or pharmacist.
Xifaxan interactions with herbs
There are currently no reports of Xifaxan interacting with herbs. But this doesn’t mean that interactions with herbs won’t be recognized in the future.
For this reason, it’s still important to check with your doctor or pharmacist before taking any of these products while taking Xifaxan.
Xifaxan interactions with vitamins
There are currently no reports of Xifaxan interacting with vitamins. But this doesn’t mean that vitamin interactions won’t be recognized in the future.
For this reason, it’s still important to check with your doctor or pharmacist before taking any of these products while taking Xifaxan.
Does Xifaxan interact with food?
There are currently no reports of Xifaxan interacting with food. If you have questions about eating certain foods during your treatment with Xifaxan, talk with your doctor.
Does this mean there are no foods to avoid while taking Xifaxan?
It depends. If you’re taking Xifaxan for irritable bowel syndrome (IBS), you may also find you feel better if you avoid certain foods. Likewise, with traveler’s diarrhea, your doctor may recommend that you stick with bland foods. If you’re taking Xifaxan to help prevent hepatic encephalopathy, your doctor may suggest that you
These recommendations are based on the condition you’re taking Xifaxan for. They aren’t due to interactions with Xifaxan.
Does Xifaxan interact with vaccines?
There are currently no reports of Xifaxan interacting with vaccines. If you have questions about getting certain vaccines during your Xifaxan treatment, talk with your doctor.
Does Xifaxan interact with lab tests?
There are currently no reports of Xifaxan interacting with lab tests. If you have questions about having certain lab tests during your treatment with Xifaxan, talk with the healthcare professional ordering the test.
Does Xifaxan interact with cannabis or CBD?Cannabis (commonly called marijuana) and cannabis products, such as cannabidiol (CBD), have been specifically reported to interact with Xifaxan. Taking Xifaxan and using cannabis can increase the risk of side effects of Xifaxan.
Before you start treatment with Xifaxan, tell your doctor and pharmacist if you use cannabis. By sharing this information with them, you may help prevent possible interactions.
Note: Cannabis is illegal at a federal level but is legal in many states to varying degrees.
Certain medical conditions or other health factors may raise the risk of interactions with Xifaxan. Before taking Xifaxan, talk with your doctor about your health history. They’ll determine whether Xifaxan is right for you.
Health conditions or other factors that might interact with Xifaxan include:
Severe liver condition. If you have a severe liver condition, such as cirrhosis, your body may not metabolize Xifaxan as well. Doctors may still prescribe Xifaxan in this case but will likely monitor you closely for side effects.
Pregnancy. It’s not known whether Xifaxan is safe to take during pregnancy. If you’re pregnant or planning a pregnancy, talk with your doctor before taking Xifaxan.
Breastfeeding. It’s not known whether it’s safe to take Xifaxan while breastfeeding. If you’re breastfeeding or planning to breastfeed, talk with your doctor about your options.
Allergic reaction. If you’ve had an allergic reaction to Xifaxan or any of its ingredients, your doctor will likely not prescribe Xifaxan. This is because taking the drug could cause another allergic reaction. You can ask your doctor about other treatments that may be better choices for you.
Taking certain steps can help you avoid interactions with Xifaxan. Before starting treatment, talk with your doctor and pharmacist. Things to discuss with them include:
- Whether you drink alcohol or use cannabis.
- Other medications you take, as well as any vitamins, supplements, and herbs. Your doctor or pharmacist can help you fill out a
medication list . - What to do if you start taking a new drug during your Xifaxan treatment.
It’s also important to understand Xifaxan’s
If you have trouble reading or understanding this information, your doctor or pharmacist can help.
Taking Xifaxan exactly as prescribed can also help prevent interactions.
If you still have questions about Xifaxan and its possible interactions, talk with your doctor.
Questions you may want to ask your doctor include:
- How do interactions with Xifaxan compare with other drugs that can treat my condition?
- If Xifaxan interacts with a drug I take, would prescribing a lower dose decrease the risk of interactions?
- Are there specific side effects I should watch for if I need to take Xifaxan with an interacting medication?
- Are there foods to avoid while taking Xifaxan?
To learn more about Xifaxan, see these articles:
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Disclaimer: Healthline 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.