Rifaximin
Rifaximin (CAS 80621-81-4) is a semi-synthetic antibiotic with the molecular formula C43H51N3O11 and a molecular weight of 785.88 g/mol. This rifamycin derivative exhibits broad-spectrum antibacterial activity. It functions by inhibiting bacterial RNA synthesis. Rifaximin is primarily recognised for its role in treating certain gastrointestinal conditions, particularly those responsive to its localised action within the gut.
- IUPAC
- 4-Deoxy-4′-methylpyrido[1′,2′-1,2]imidazo[5,4-c]rifamycin SV,Rifacol
- Synonyms
- 4-Deoxy-4′-methylpyrido[1′,2′-1,2]imidazo[5,4-c]rifamycin SVRifacol

Antibacterial Agent
Rifaximin is a potent antibacterial compound used to combat a range of bacterial infections. Its mechanism of action involves the inhibition of bacterial DNA-dependent RNA polymerase, thereby halting RNA and protein synthesis.
Gastrointestinal Treatments
This compound is recognised for its utility in managing specific gastrointestinal disorders. Its limited systemic absorption allows for targeted action within the intestinal lumen, making it effective for conditions like travellers' diarrhoea and hepatic encephalopathy.
Analytical Standard
As an analytical standard, Rifaximin is employed in chromatographic and spectroscopic methods for the identification, quantification, and quality control of pharmaceutical formulations and related substances.
| Molecular weight | 785.88 |
|---|---|
| Empirical formula | C43H51N3O11 |
| Grade | VETRANAL™, analytical standard |
| Storage temperature | 2-8°C |
| Protective equipment | Eyeshields, Gloves, type N95 (US), type P1 (EN143) respirator filter |
|---|---|
| Water hazard class (WGK, DE) | 2 |
Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.
Documentation
Every batch ships with a Certificate of Analysis covering assay, identity and purity; the grade is confirmed against your enquiry. Safety Data Sheets and technical data sheets are available on request.
Supply & logistics
Samples for technical evaluation; bulk MOQ by grade and packaging. In-stock material ships in 7–10 working days, worldwide, with full export documentation.
What is Rifaximin used for?
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Rifaximin is primarily used as an antibacterial agent for treating certain gastrointestinal conditions, such as travellers' diarrhoea and hepatic encephalopathy, and also serves as an analytical standard.
What is the CAS number and formula for Rifaximin?
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The CAS number for Rifaximin is 80621-81-4, and its empirical formula is C43H51N3O11.
What grade and purity does Tech Serve Solutions supply?
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Tech Serve Solutions supplies Rifaximin as a VETRANAL™, analytical standard. We do not represent this product as USP, BP, or EP grade.
How should Rifaximin be handled and stored?
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When handling Rifaximin, it is essential to wear eyeshields and gloves. A type N95 (US) or type P1 (EN143) respirator filter is recommended. Store Rifaximin at temperatures between 2-8°C.
Is Rifaximin a controlled substance?
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The provided data does not indicate that Rifaximin is a controlled substance.
How can I request a sample or quote for Rifaximin?
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To request a sample or a quote for Rifaximin, please contact our sales department through the website or by phone.
How is Rifaximin packed, shipped, and exported?
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Rifaximin is carefully packed to ensure stability during transit and is available for global export by Tech Serve Solutions.
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