Xifaxan (rifaximin) runs about $3,100 for a standard supply at retail price, making it one of the most expensive antibiotics on the market. Cheaper alternatives exist, but the right one depends on why you’re taking it. Xifaxan is prescribed for three main conditions: irritable bowel syndrome with diarrhea (IBS-D), hepatic encephalopathy (a liver-related brain condition), and traveler’s diarrhea. Each has a different set of lower-cost options.
When Generic Rifaximin Might Arrive
The FDA has tentatively approved at least one generic version of rifaximin, confirming it’s bioequivalent to Xifaxan. But “tentatively approved” means it can’t be sold yet. Patents on the 200 mg tablet don’t expire until July 2029 at the earliest. The 550 mg tablet, which is the strength used for IBS-D and hepatic encephalopathy, faces an additional delay: another generic manufacturer submitted an application first and holds 180 days of market exclusivity once it launches. So even after patent expiration, there will be a waiting period before multiple generics compete and drive prices down significantly.
In short, a true generic equivalent is still years away.
Alternatives for IBS-D
If you’re taking Xifaxan for IBS-D, you have several options that cost a fraction of the price. In fact, most insurers require you to try cheaper medications first before they’ll approve Xifaxan at all.
Low-dose tricyclic antidepressants like amitriptyline are a common first-line treatment. These are old, inexpensive generic drugs that slow gut motility and reduce pain signaling in the digestive tract. They typically cost under $20 a month. Your insurer will likely require that you try one before covering Xifaxan.
Eluxadoline (brand name Viberzi) is another prescription option specifically approved for IBS-D. It works by slowing intestinal contractions and reducing pain signals in the gut. Side effects include nausea (8 to 10%), constipation (6 to 7%), and abdominal pain (6 to 7%). Viberzi isn’t cheap either, but it’s generally less expensive than Xifaxan and is often the next step insurers want you to try. Alosetron is a more restricted option available only to women with severe IBS-D who haven’t responded to other treatments.
Over-the-counter loperamide (Imodium) can manage diarrhea symptoms at minimal cost, though it doesn’t address the underlying bacterial overgrowth that Xifaxan targets.
Herbal Antimicrobials for SIBO
If your doctor prescribed Xifaxan for small intestinal bacterial overgrowth (SIBO), herbal antimicrobial combinations may be worth discussing. A study published in Global Advances in Health and Medicine compared herbal therapy to rifaximin and found comparable results: 46% of patients on herbal treatment had a negative breath test afterward, compared to 34% on rifaximin. The difference wasn’t statistically significant, meaning the two approaches performed similarly.
The herbal protocols used in the study were specific commercial products: Candibactin-AR paired with Candibactin-BR (made by Metagenics), or Dysbiocide paired with FC Cidal (made by Biotics Research). The active ingredients include oregano oil, berberine, thyme oil, and several traditional botanical extracts. A four-week course of these supplements typically runs $50 to $100, depending on the retailer.
Perhaps most interesting: among patients who didn’t respond to rifaximin, 57% responded to herbal therapy as a follow-up treatment. This suggests the herbals work through slightly different mechanisms and can serve as a viable backup plan, not just a first-line substitute.
These are not random herbs from the supplement aisle. The protocols involve specific products at specific doses, so work with a gastroenterologist or integrative medicine provider who’s familiar with the research rather than self-prescribing.
Alternatives for Hepatic Encephalopathy
Lactulose is the classic alternative here, and it’s dramatically cheaper. A month’s supply of lactulose typically costs $15 to $40 at most pharmacies. It works by pulling ammonia out of your bloodstream through the gut, preventing the toxic buildup that causes confusion and cognitive problems in people with liver disease.
However, lactulose and rifaximin aren’t equal. In a prospective comparative study, hepatic encephalopathy recurred in about 17% of patients on rifaximin versus 35% on lactulose. Hospitalizations related to the condition were also significantly lower with rifaximin (13% vs. 31%). Patients on rifaximin maintained clarity for an average of 5.6 months before any recurrence, compared to 4.3 months with lactulose.
Tolerability is the other major difference. Lactulose causes diarrhea in about 27% of users, bloating in 15%, and nausea in 12%. Rifaximin causes those same side effects in fewer than 7% of patients. About 6% of lactulose users stop treatment because of side effects, compared to less than 1% on rifaximin. This matters because the medication only works if you keep taking it.
Most insurance plans actually structure coverage around this gap. UnitedHealthcare’s policy, which is typical of major insurers, approves Xifaxan for hepatic encephalopathy only when it’s added to lactulose that isn’t working well enough on its own, or when a patient can’t tolerate lactulose. So many patients end up on both medications together, with lactulose covering the baseline and rifaximin providing additional protection.
Alternatives for Traveler’s Diarrhea
This is the easiest condition to find a cheap substitute for. Several generic antibiotics treat traveler’s diarrhea effectively, and insurers require you to try one before approving Xifaxan. The standard options are ciprofloxacin, azithromycin, and levofloxacin, all available as generics for under $20. Azithromycin is often the first choice because of its broad effectiveness and short treatment course.
Ways to Lower the Cost of Xifaxan Itself
If your condition genuinely calls for rifaximin and alternatives haven’t worked, several programs can reduce your out-of-pocket cost substantially.
Bausch, the company that makes Xifaxan, runs a patient assistance program for people without insurance coverage for the drug. Eligibility is based on household income and size, U.S. residency, and whether you’ve been denied Medicaid. You’ll need to go through their online questionnaire with income documentation to find out if you qualify. If approved, you may receive the medication at no cost.
Pharmacy discount cards through GoodRx and similar services can reduce the retail price, though for a drug this expensive, the savings may still leave you with a significant bill. Manufacturer copay cards are sometimes available for commercially insured patients and can reduce copays to a more manageable level.
Buying From International Pharmacies
Rifaximin is available in other countries at much lower prices, and some patients consider ordering from online pharmacies in Canada or India. This carries real risks. According to Health Canada’s guidance, health products sold online may be counterfeit, contain incorrect doses of the active ingredient, or include toxic contaminants. Websites that appear to be based in Canada sometimes operate from elsewhere, making it difficult to verify legitimacy.
From a legal perspective, the FDA generally does not approve personal importation of prescription drugs, though enforcement varies. If you go this route, you’re accepting uncertainty about what you’re actually receiving, with no regulatory safety net if something is wrong with the product.
Navigating Insurance Prior Authorization
If your doctor believes Xifaxan is the right treatment, understanding what your insurer requires can save weeks of back-and-forth. Most plans use “step therapy,” meaning you need documented failure of cheaper drugs before they’ll cover Xifaxan. Based on UnitedHealthcare’s criteria, which mirror most major insurers:
- For IBS-D: You’ll need to have tried and failed both a tricyclic antidepressant and eluxadoline (or have a documented reason you can’t take them).
- For hepatic encephalopathy: You’ll need to show that lactulose alone isn’t controlling your symptoms, or that you can’t tolerate it.
- For traveler’s diarrhea: You’ll need documented failure or intolerance of a generic antibiotic like ciprofloxacin or azithromycin.
Keep records of every medication you’ve tried, how long you took it, and what happened. Your doctor’s office will need this documentation when submitting the prior authorization. A denied claim can often be overturned on appeal if the paperwork clearly shows you’ve met the step therapy requirements.