Generic Xifaxan Availability

Last updated on Apr 10, 2025.

Xifaxan is a brand name of rifaximin, approved by the FDA in the following formulation(s):

XIFAXAN (rifaximin - tablet;oral)

Manufacturer: SALIX PHARMS
Approval date: May 25, 2004
Strength(s): 200MG ^[RLD]
Manufacturer: SALIX PHARMS
Approval date: March 24, 2010
Strength(s): 550MG ^[RLD]

Is there a generic version of Xifaxan available?

No. There is currently no therapeutically equivalent version of Xifaxan available in the United States.

Note: Fraudulent online pharmacies may attempt to sell an illegal generic version of Xifaxan. These medications may be counterfeit and potentially unsafe. If you purchase medications online, be sure you are buying from a reputable and valid online pharmacy. Ask your health care provider for advice if you are unsure about the online purchase of any medication.

Related patents

Patents are granted by the U.S. Patent and Trademark Office at any time during a drug's development and may include a wide range of claims.

Methods of treating hepatic encephalopathy
Patent 10,314,828
Issued: June 11, 2019
Inventor(s): Forbes William & Merchant Kunal & Bortey Enoch & Shaw Audrey
Assignee(s): Salix Pharmaceuticals, Ltd
The application describes treatment of hepatic encephalopathy using gastrointestinal specific antibiotics. One example of a gastrointestinal specific antibiotic is rifaximin. The instant application also provides methods for determining if a subject has a neurological condition or hepatic encephalopathy by determining the critical flicker frequency and/or the venous ammonia level of the subject at two or more time points. The invention further provides methods for treating these subjects.
Patent expiration dates:
- July 24, 2029
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  Patent use: REDUCTION IN RISK OF OVERT HEPATIC ENCEPHALOPATHY (HE) RECURRENCE
Methods of treating hepatic encephalopathy
Patent 10,335,397
Issued: July 2, 2019
Inventor(s): Forbes William
Assignee(s): Salix Pharmaceuticals, Ltd
The application describes treatment of hepatic encephalopathy using gastrointestinal specific antibiotics. One example of a gastrointestinal specific antibiotic is rifaximin.
Patent expiration dates:
- July 24, 2029
  ✓
  Patent use: REDUCTION IN A SUBJECT'S RISK OF EXPERIENCING A BREAKTHROUGH OVERT HEPATIC ENCEPHALOPATHY (HE) EPISODE
Methods for treating irritable bowel syndrome (IBS)
Patent 10,456,384
Issued: October 29, 2019
Inventor(s): Forbes William & Bortey Enoch
Assignee(s): Salix Pharmaceuticals, Inc.
The present invention provides new methods and kits for treating IBS; treating IBS in females; treating IBS in older subjects; and treating IBS in non-white subjects.
Patent expiration dates:
- February 26, 2029
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  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS 65 YEARS OF AGE OR OLDER AND SYMPTOMS THEREOF
- February 26, 2029
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  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS 65 YEARS OF AGE OR OLDER
Polymorphous forms of rifaximin, processes for their production and use thereof in the medicinal preparations
Patent 10,703,763
Issued: July 7, 2020
Inventor(s): Viscomi Giuseppe Claudio & Campana Manuela & Confortini Donatella & Barbanti Maria & Braga Dario
Assignee(s): ALFASIGMA S.P.A.
Crystalline polymorphous forms of the rifaximin (INN) antibiotic named rifaximin δ and rifaximin ε useful in the production of medicinal preparations containing rifaximin for oral and topical use and obtained by means of a crystallization process carried out by hot-dissolving the raw rifaximin in ethyl alcohol and by causing the crystallization of the product by addition of water at a determinate temperature and for a determinate period of time, followed by a drying carried out under controlled conditions until reaching a settled water content in the end product, are the object of the invention.
Patent expiration dates:
- February 27, 2026
  ✓
  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS.
- February 27, 2026
  ✓
  Patent use: REDUCTION IN RISK OF OVERT HEPATIC ENCEPHALOPATHY (HE) RECURRENCE IN ADULTS
- February 27, 2026
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  Patent use: TREATMENT OF TRAVELERS' DIARRHEA (TD) CAUSED BY NONINVASIVE STRAINS OF ESCHERIA COLI IN ADULT AND PEDIATRIC PATIENTS 12 YEARS OF AGE AND OLDER
Methods of treating hepatic encephalopathy
Patent 10,709,694
Issued: July 14, 2020
Inventor(s): Forbes William
Assignee(s): Salix Pharmaceuticals, Inc.
The application describes treatment of hepatic encephalopathy using gastrointestinal specific antibiotics. One example of a gastrointestinal specific antibiotic is rifaximin.
Patent expiration dates:
- July 24, 2029
  ✓
  Patent use: REDUCTION IN A SUBJECT'S RISK OF EXPERIENCING A BREAKTHROUGH OVERT HEPATIC ENCEPHALOPATHY (HE) EPISODE
Methods for treating irritable bowel syndrome (IBS)
Patent 10,765,667
Issued: September 8, 2020
Inventor(s): Forbes William & Bortey Enoch
Assignee(s): Salix Pharmaceuticals, Inc.
The present invention provides new methods and kits for treating IBS; treating IBS in females; treating IBS in older subjects; and treating IBS in non-white subjects.
Patent expiration dates:
- February 26, 2029
  ✓
  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS 65 YEARS OF AGE OR OLDER AND SYMPTOMS THEREOF
- February 26, 2029
  ✓
  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS 65 YEARS OF AGE OR OLDER
Methods for treating irritable bowel syndrome (IBS)
Patent 11,564,912
Issued: January 31, 2023
Inventor(s): Forbes; William P. et al.
Assignee(s): Salix Pharmaceuticals, Inc. (Bridgewater, NJ)
The present invention provides new methods and kits for treating IBS; treating IBS in females; treating IBS in older subjects; and treating IBS in non-white subjects.
Patent expiration dates:
- February 26, 2029
  ✓
  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULT FEMALE SUBJECTS AND SYMPTOMS THEREOF
- February 26, 2029
  ✓
  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULT FEMALE SUBJECTS
Methods for treating irritable bowel syndrome (IBS)
Patent 11,779,571
Issued: October 10, 2023
Inventor(s): Forbes; William et al.
Assignee(s): Salix Pharmaceuticals, Inc. (Bridgewater, NJ)
The present invention provides new methods and kits for treating IBS; treating IBS in females; treating IBS in older subjects; and treating IBS in non-white subjects.
Patent expiration dates:
- February 26, 2029
  ✓
  Patent use: TREATMENT OF BLOATING ASSOCIATED WITH DIARRHEA-PREDOMINANT IRRITABLE BOWEL SYNDROME (IBS-D) IN ADULT FEMALE SUBJECTS
Pharmaceutical compositions comprising polymorphic forms .alpha., .beta., and .gamma. of rifaximin
Patent 7,906,542
Issued: March 15, 2011
Inventor(s): Viscomi; Giuseppe Claudio et al.
Assignee(s): Alfa Wassermann, S.p.A. (Bologna, IT)
Crystalline polymorphous forms of rifaximin (INN), referred to as rifaximin .alpha. and rifaximin .beta., and a poorly crystalline form referred to as rifaximin .gamma., useful in the production of medicaments containing rifaximin for oral and topical use and obtained by means of a crystallization process carried out by hot-dissolving the raw rifaximin in ethyl alcohol and by causing the crystallization of the product by addition of water at a fixed temperature and for a fixed period of time, followed by a drying under controlled conditions until reaching a precise water content in the end product, are the object of the invention.
Patent expiration dates:
- June 1, 2025
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Use of polymorphic forms of rifaximin for medical preparations
Patent 7,915,275
Issued: March 29, 2011
Inventor(s): Viscomi; Giuseppe C. et al.
Assignee(s): Alfa Wassermann, S.p.A. (Bologna, IT)
The present invention relates to Rifaximin polymorphic forms .alpha., .beta. and .gamma., to their use in medicinal preparations for the oral or topical route and to therapeutic methods using them.
Patent expiration dates:
- February 23, 2025
  ✓
  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS AND SYMPTOMS THEREOF.
- February 23, 2025
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  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS.
Methods of treating travelers diarrhea and hepatic encephalopathy
Patent 7,928,115
Issued: April 19, 2011
Inventor(s): Forbes; William et al.
Assignee(s): Salix Pharmaceuticals, Ltd. (Morrisville, NC)
Treatment of traveler's diarrhea in subjects having hepatic encephalopathy using rifaximin is disclosed.
Patent expiration dates:
- July 24, 2029
  ✓
  Patent use: METHOD OF TREATING TRAVELERS' DIARRHEA
Polymorphous forms of rifaximin, processes for their production and use thereof in the medicinal preparations
Patent 8,193,196
Issued: June 5, 2012
Inventor(s): Viscomi Giuseppe Claudio & Campana Manuela & Confortini Donatella & Barbanti Maria Miriam & Braga Dario
Assignee(s): Alfa Wassermann, S.p.A.
Crystalline polymorphous forms of the rifaximin (INN) antibiotic named rifaximin δ and rifaximin ε useful in the production of medicinal preparations containing rifaximin for oral and topical use and obtained by means of a crystallization process carried out by hot-dissolving the raw rifaximin in ethyl alcohol and by causing the crystallization of the product by addition of water at a determinate temperature and for a determinate period of time, followed by a drying carried out under controlled conditions until reaching a settled water content in the end product, are the object of the invention.
Patent expiration dates:
- September 2, 2027
  ✓
  Drug substance
  ✓
  Drug product
- September 2, 2027
  ✓
  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS AND SYMPTOMS THEREOF.
  ✓
  Drug substance
  ✓
  Drug product
- September 2, 2027
  ✓
  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS.
  ✓
  Drug substance
  ✓
  Drug product
Methods for treating diarrhea-associated irritable bowel syndrome
Patent 8,309,569
Issued: November 13, 2012
Inventor(s): Forbes William & Johnson Lorin
Assignee(s): Salix Pharmaceuticals, Ltd.
The present invention provides methods of treating diarrhea-associated irritable bowel syndrome (IBS-D) following rifaximin administration.
Patent expiration dates:
- July 18, 2029
  ✓
  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS AND SYMPTOMS THEREOF.
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  Sponsor has requested patent be delisted
- July 18, 2029
  ✓
  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS.
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  Sponsor has requested patent be delisted
Polymorphous forms of rifaximin, processes for their production and use thereof in the medicinal preparations
Patent 8,518,949
Issued: August 27, 2013
Inventor(s): Viscomi Giuseppe Claudio & Campana Manuela & Confortini Donatella & Barbanti Maria Miriam & Braga Dario
Assignee(s): ALFA Wassermann S.p.A.
Crystalline polymorphous forms of the rifaximin (INN) antibiotic named rifaximin δ and rifaximin ε useful in the production of medicinal preparations containing rifaximin for oral and topical use and obtained by means of a crystallization process carried out by hot-dissolving the raw rifaximin in ethyl alcohol and by causing the crystallization of the product by addition of water at a determinate temperature and for a determinate period of time, followed by a drying carried out under controlled conditions until reaching a settled water content in the end product, are the object of the invention.
Patent expiration dates:
- February 27, 2026
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  Drug product
Methods of treating hepatic encephalopathy
Patent 8,642,573
Issued: February 4, 2014
Inventor(s): Forbes William & Merchant Kunal & Bortey Enoch & Shaw Audrey
Assignee(s): Salix Pharmaceuticals, Ltd
The application describes treatment of hepatic encephalopathy using gastrointestinal specific antibiotics. One example of a gastrointestinal specific antibiotic is rifaximin. The instant application also provides methods for determining if a subject has a neurological condition or hepatic encephalopathy by determining the critical flicker frequency and/or the venous ammonia level of the subject at two or more time points. The invention further provides methods for treating these subjects.
Patent expiration dates:
- October 2, 2029
  ✓
  Patent use: REDUCTION IN RISK OF OVERT HEPATIC ENCEPHALOPATHY (HE) RECURRENCE
Polymorphous forms of rifaximin, processes for their production and use thereof in the medicinal preparations
Patent 8,741,904
Issued: June 3, 2014
Inventor(s): Viscomi Giuseppe Claudio & Campana Manuela & Confortini Donatella & Barbanti Maria & Braga Dario
Assignee(s): Alfa Wassermann S.p.A.
Crystalline polymorphous forms of the rifaximin (INN) antibiotic named rifaximin δ and rifaximin ε useful in the production of medicinal preparations containing rifaximin for oral and topical use and obtained by means of a crystallization process carried out by hot-dissolving the raw rifaximin in ethyl alcohol and by causing the crystallization of the product by addition of water at a determinate temperature and for a determinate period of time, followed by a drying carried out under controlled conditions until reaching a settled water content in the end product, are the object of the invention.
Patent expiration dates:
- February 27, 2026
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  Patent use: THE TREATMENT OF PATIENTS WITH TRAVELERS' DIARRHEA (TD) OR THE REDUCTION IN RISK OF OVERT HEPATIC ENCEPHALOPATHY (HE) RECURRENCE
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  Drug substance
- February 27, 2026
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  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS AND SYMPTOMS THEREOF.
  ✓
  Drug substance
- February 27, 2026
  ✓
  Patent use: TREATMENT OF IRRITABLE BOWEL SYNDROME WITH DIARRHEA (IBS-D) IN ADULTS.
  ✓
  Drug substance
Methods of treating traveler's diarrhea and hepatic encephalopathy
Patent 8,829,017
Issued: September 9, 2014
Inventor(s): Forbes William & Bortey Enoch
Assignee(s): Salix Pharmaceuticals, Ltd.
Treatment of traveler's diarrhea using in subjects having hepatic encephalopathy using gastrointestinal specific antibiotics is disclosed. One example of a gastrointestinal specific antibiotic is rifaximin.
Patent expiration dates:
- July 24, 2029
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  Patent use: TREATMENT OF PATIENTS WITH HEPATIC ENCEPHALOPATHY (HE)
Methods of treating traveler's diarrhea and hepatic encephalopathy
Patent 8,946,252
Issued: February 3, 2015
Inventor(s): Forbes William & Bortey Enoch
Assignee(s): Salix Pharmaceuticals, Ltd
Treatment of traveler's diarrhea using in subjects having hepatic encephalopathy using gastrointestinal specific antibiotics is disclosed. One example of a gastrointestinal specific antibiotic is rifaximin.
Patent expiration dates:
- July 24, 2029
  ✓
  Patent use: REDUCTION IN RISK OF OVERT HEPATIC ENCEPHALOPATHY (HE) RECURRENCE
Methods of treating hepatic encephalopathy
Patent 8,969,398
Issued: March 3, 2015
Inventor(s): Forbes William
Assignee(s): Salix Pharmaceuticals, Ltd.
The application describes treatment of hepatic encephalopathy using gastrointestinal specific antibiotics. One example of a gastrointestinal specific antibiotic is rifaximin.
Patent expiration dates:
- October 2, 2029
  ✓
  Patent use: REDUCTION IN RISK OF OVERT HEPATIC ENCEPHALOPATHY (HE) RECURRENCE
Polymorphous forms of rifaximin, processes for their production and use thereof in the medicinal preparations
Patent 9,271,968
Issued: March 1, 2016
Inventor(s): Viscomi Giuseppe Claudio & Campana Manuela & Confortini Donatella & Barbanti Maria & Braga Dario
Assignee(s): ALFA WASSERMANN S.P.A.
Crystalline polymorphous forms of the rifaximin (INN) antibiotic named rifaximin δ and rifaximin ε useful in the production of medicinal preparations containing rifaximin for oral and topical use and obtained by means of a crystallization process carried out by hot-dissolving the raw rifaximin in ethyl alcohol and by causing the crystallization of the product by addition of water at a determinate temperature and for a determinate period of time, followed by a drying carried out under controlled conditions until reaching a settled water content in the end product, are the object of the invention.
Patent expiration dates:
- February 27, 2026
  ✓
  Drug product
Methods of treating hepatic encephalopathy
Patent 9,421,195
Issued: August 23, 2016
Inventor(s): Forbes William & Merchant Kunal & Bortey Enoch & Shaw Audrey
Assignee(s): Salix Pharmaceuticals, Ltd
The application describes treatment of hepatic encephalopathy using gastrointestinal specific antibiotics. One example of a gastrointestinal specific antibiotic is rifaximin. The instant application also provides methods for determining if a subject has a neurological condition or hepatic encephalopathy by determining the critical flicker frequency and/or the venous ammonia level of the subject at two or more time points. The invention further provides methods for treating these subjects.
Patent expiration dates:
- July 24, 2029
  ✓
  Patent use: REDUCTION IN RISK OF OVERT HEPATIC ENCEPHALOPATHY (HE) RECURRENCE
Methods of treating traveler's diarrhea and hepatic encephalopathy
Patent 9,629,828
Issued: April 25, 2017
Inventor(s): Forbes William & Bortey Enoch
Assignee(s): Salix Pharmaceuticals, Ltd.
Treatment of traveler's diarrhea using in subjects having hepatic encephalopathy using gastrointestinal specific antibiotics is disclosed. One example of a gastrointestinal specific antibiotic is rifaximin.
Patent expiration dates:
- July 24, 2029
  ✓
  Patent use: REDUCTION IN RISK OF OVERT HEPATIC ENCEPHALOPATHY (HE) IN ADULTS

More about Xifaxan (rifaximin)

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Glossary

Term	Definition
Drug Patent	A drug patent is assigned by the U.S. Patent and Trademark Office and assigns exclusive legal right to the patent holder to protect the proprietary chemical formulation. The patent assigns exclusive legal right to the inventor or patent holder, and may include entities such as the drug brand name, trademark, product dosage form, ingredient formulation, or manufacturing process A patent usually expires 20 years from the date of filing, but can be variable based on many factors, including development of new formulations of the original chemical, and patent infringement litigation.
Drug Exclusivity	Exclusivity is the sole marketing rights granted by the FDA to a manufacturer upon the approval of a drug and may run simultaneously with a patent. Exclusivity periods can run from 180 days to seven years depending upon the circumstance of the exclusivity grant.
RLD	A Reference Listed Drug (RLD) is an approved drug product to which new generic versions are compared to show that they are bioequivalent. A drug company seeking approval to market a generic equivalent must refer to the Reference Listed Drug in its Abbreviated New Drug Application (ANDA). By designating a single reference listed drug as the standard to which all generic versions must be shown to be bioequivalent, FDA hopes to avoid possible significant variations among generic drugs and their brand name counterpart.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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Drug Status

Availability Prescription only Rx

Pregnancy & Lactation Risk data available

CSA Schedule* Not a controlled drug N/A

Approval History Drug history at FDA

User Reviews & Ratings

6.5 / 10

95 Reviews

Images

Pill rfx is Xifaxan 550 mg — Xifaxan 550 mg (rfx)