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Xifaxan Side Effects: What You Need to Know

In This Article

What Is Xifaxan and How Does It Work?

Xifaxan (rifaximin) is a unique antibiotic that works differently from most other antibiotics you might know. Unlike typical antibiotics that travel throughout your entire body, Xifaxan stays mostly in your digestive tract. This makes it useful for treating certain gut-related conditions while reducing the risk of some side effects.

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The medication is FDA-approved to treat three main conditions: irritable bowel syndrome with diarrhea (IBS-D), traveler’s diarrhea caused by certain bacteria, and hepatic encephalopathy (a liver-related brain condition). Because it primarily acts in the gut rather than being absorbed into the bloodstream, Xifaxan has a different side effect profile compared to other antibiotics.

Common Side Effects of Xifaxan

Most people who take Xifaxan experience mild side effects, if any at all. The most frequently reported side effects include digestive symptoms, which makes sense given that the medication works in your gut.

Digestive Side Effects

The most common side effects include:

  • Nausea: Feeling queasy or sick to your stomach.
  • Abdominal pain: Cramping or discomfort in your belly area.
  • Bloating: Feeling full or swollen in your abdomen.
  • Gas: Increased flatulence or feeling gassy.
  • Constipation: Difficulty having bowel movements.
  • Vomiting: Actually being sick to your stomach.

These symptoms are typically mild and often improve as your body adjusts to the medication.

General Side Effects

Beyond digestive issues, some people experience:

  • Headache: Often mild and temporary.
  • Dizziness: Feeling lightheaded or unsteady.
  • Fatigue: Feeling more tired than usual.
  • Swelling: Particularly in hands, feet, or ankles.

Serious but Rare Side Effects

While most people tolerate Xifaxan well, some serious side effects occur rarely but require immediate medical attention.

Clostridioides Difficile Infection

Like other antibiotics, Xifaxan can potentially lead to C. diff infection, though this is uncommon. This serious condition occurs when harmful bacteria overgrow in your colon after antibiotics kill off protective bacteria. Symptoms include:

  • Severe, persistent diarrhea
  • Abdominal cramping and pain
  • Blood or mucus in stool
  • Fever
  • Rapid heart rate

Severe Allergic Reactions

Though rare, some people may experience serious allergic reactions to rifaximin, including:

  • Difficulty breathing or swallowing
  • Swelling of face, lips, tongue, or throat
  • Severe skin rash or hives
  • Rapid heartbeat
  • Dizziness or fainting

If you experience any of these symptoms, seek emergency medical care immediately.

Who Should Be Cautious About Taking Xifaxan?

Liver Function Considerations

While Xifaxan is often prescribed for liver-related conditions, patients with severe liver problems need careful monitoring. The medication can affect how your liver processes other drugs, and liver function may influence how your body handles Xifaxan itself.

Pregnancy and Breastfeeding

There is limited information about the safety of using Xifaxan during pregnancy and breastfeeding. However, some animal studies have shown potential risks of harm to your unborn baby. Always discuss with your healthcare provider if you are pregnant, planning to become pregnant, or breastfeeding.

Kidney Function

Patients with kidney problems can generally take Xifaxan safely, since very little of the medication is absorbed into the bloodstream. However, your doctor may still want to monitor you more closely.

Drug Interactions and Precautions

Xifaxan can interact with certain medications, though interactions are less common than with other antibiotics because so little is absorbed into your bloodstream.

Blood Thinners

Xifaxan may increase the effects of warfarin and other blood-thinning medications. If you take blood thinners, your doctor may need to monitor your blood clotting times more frequently.

P-glycoprotein (P-gp) Inhibitors

Some drugs decrease the activity of a protein called P-glycoprotein (P-gp). This protein helps remove certain medications from your body, including Xifaxan. Some drugs to look out for include:

  • clarithromycin (Biaxin)
  • erythromycin (Ery-tab)
  • glecaprevir/pibrentasvir (Mavyret)
  • ledipasvir/sofosbuvir (Harvoni)
  • sofosbuvir/velpatasvir/voxilaprevir (Vosevi)
  • cobicistat (Tybost) and meds that contain cobicistat
  • ritonavir (Norvir) and meds that contain ritonavir
  • cyclosporine (Gengraf, Neoral, Sandimmune)

Managing Side Effects While Taking Xifaxan

Digestive Comfort

If you experience nausea or stomach upset:

  • Take Xifaxan with food to reduce stomach irritation
  • Eat smaller, more frequent meals
  • Avoid spicy, fatty, or very rich foods
  • Stay hydrated with clear fluids
  • Consider probiotics after completing treatment (discuss with your doctor first)

When to Contact Your Doctor

Call your healthcare provider if you experience:

  • Side effects that worsen or don’t improve after a few days
  • New symptoms that concern you
  • Signs of C. diff infection
  • Any allergic reaction symptoms
  • Unusual changes in your bowel habits

Cost Considerations and Accessing Xifaxan

Xifaxan can be expensive, especially for patients without adequate insurance coverage. The medication is often prescribed for conditions that require repeated courses of treatment, which can add up significantly over time.

For patients concerned about cost, exploring cash-pay options through trusted sources like Universal Drugstore can provide access to more affordable pricing. Many patients find that paying cash directly can sometimes be less expensive than using insurance, particularly if you have a high deductible or limited prescription coverage.

Patient assistance programs may also be available through the manufacturer for qualifying individuals. Your healthcare provider or pharmacist can help you explore these options.

Long-Term Safety and Repeated Use

One advantage of Xifaxan is that it can often be used repeatedly when needed. For IBS-D, some patients may need multiple courses of treatment over time. For hepatic encephalopathy prevention, some patients take it continuously for months or years.

Long-term studies suggest that Xifaxan maintains its safety profile with repeated use. However, your doctor will monitor you regularly to ensure the medication continues to be appropriate and effective for your condition.

Resistance Concerns

Because Xifaxan works locally in the gut and has a unique mechanism of action, the development of bacterial resistance appears to be less of a concern compared to systemic antibiotics. However, it’s still important to take the medication exactly as prescribed.

What to Expect During Treatment

Timeline for Side Effects

Most side effects from Xifaxan appear within the first few days of starting treatment. The good news is that many side effects are temporary and improve as your body adjusts to the medication. If you’re taking a short course (like the typical 14-day treatment for IBS-D), side effects usually resolve shortly after completing treatment.

Monitoring Your Response

Keep track of both your symptoms and any side effects you experience. This information helps your healthcare provider determine if Xifaxan is working well for you and whether any adjustments to your treatment plan are needed.

Your doctor may want to see you during treatment or shortly after to assess how you’re responding. Be honest about any side effects you experience, even if they seem minor. Sometimes adjusting the timing of doses or taking the medication with food can help reduce uncomfortable side effects.

Bottom Line: Weighing Benefits and Risks

Xifaxan generally has a favorable side effect profile compared to many other antibiotics. Most people who take it experience only mild, temporary side effects, if any at all. The medication’s unique property of staying in the gut rather than being absorbed throughout the body contributes to its relatively gentle side effect profile.

For conditions like IBS-D and hepatic encephalopathy, many patients find that the benefits of Xifaxan significantly outweigh the potential side effects. The key is working closely with your healthcare provider to monitor your response and address any concerns that arise during treatment.

Remember that everyone responds differently to medications. What one person experiences may be completely different from what you experience. The most important thing is to stay informed, communicate openly with your healthcare team, and seek medical attention if you have any concerns about serious side effects.

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