≥97% (HPLC), powder

Rifampin, Rifamycin AMP, 3-(4-Methylpiperazinyliminomethyl)rifamycin SV
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:
Beilstein/REAXYS Number:
EC Number:
MDL number:
PubChem Substance ID:

Quality Level


≥97% (HPLC)




faintly orange to red-brown


1.7 (4-hydroxyl group)
7.9 (4-piperazine nitrogen)




H2O: 1.3 mg/mL (pH 4.3)
DMSO: 100 mg/mL
H2O: 2.5 mg/mL at 25 °C (pH 7.3)
chloroform: soluble 50 mg/mL

Mode of action

protein synthesis | interferes

antibiotic activity spectrum

Gram-negative bacteria
Gram-positive bacteria

storage temp.


SMILES string




InChI key


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General description

Chemical structure: macrolide


Rifampicin is used to treat Tuberculosis and Tuberculosis-related mycobacterial infections. It is widely used as an antipruritic agent in the autoimmune cholestatic liver disease, primary biliary cirrhosis (PBC). It has been shown to cause hepatitis.


250 mg in glass insert
1, 5, 25 g in glass bottle

Biochem/physiol Actions

Rifampicin inhibits the assembly of DNA and protein into mature virus particles. It inhibits initiation of RNA synthesis by binding to β-subunit of RNA polymerase, which results in cell death.
Mode of Action: Inhibits initiation of RNA synthesis by binding to β-subunit of RNA polymerase.
Inhibits the assembly of DNA and protein into mature virus particles.

Other Notes

Keep container tightly closed in a dry and well-ventilated place.Product is sensitive to light and moisture.Store under inert gas. Keep in a dry place


Exclamation mark

Signal Word


Target Organs

Respiratory system

Personal Protective Equipment

dust mask type N95 (US),Eyeshields,Gloves


NONH for all modes of transport

WGK Germany


Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis

Certificate of Origin

  1. Which document(s) contains shelf-life or expiration date information for a given product?

    If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.

  2. How do I get lot-specific information or a Certificate of Analysis?

    The lot specific COA document can be found by entering the lot number above under the "Documents" section.

  3. How do I find price and availability?

    There are several ways to find pricing and availability for our products. Once you log onto our website, you will find the price and availability displayed on the product detail page. You can contact any of our Customer Sales and Service offices to receive a quote.  USA customers:  1-800-325-3010 or view local office numbers.

  4. What is the Department of Transportation shipping information for this product?

    Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product. 

  5. How is the potency determined for Product R3501, Rifampicin?

    The potency is determined from a microbiological assay (USP XXII) for antibiotics, a 2-level assay. The test organism is Bacillus subtilis ATCC 6633. The minimum dose is 4.0 μg/ml and the maximum dose is 8.0 μg/ml.

  6. The label advises that I should store Product R3501, Rifampicin, frozen. But when it arrived there was no ice in the package. Why is that?

    This product in its powder form is stable for short periods of time (i.e., the shipping process), at ambient temperature.  For long term storage it is best to store it at -20°C.

  7. What is the difference between the various Rifampicin products available from Sigma-Aldrich?

    Sigma-Aldrich offers several Rifampicin products, each tested and best suited for specific applications.  The products range from a general use research grade to sterile powder, to plant culture tested.  See individual products for specific details.

  8. My question is not addressed here, how can I contact Technical Service for assistance?

    Ask a Scientist here.

  9. My question is not addressed here, how can I contact Technical Service for assistance?

    Ask a Scientist here.

M I Prince et al.
Gut, 50(3), 436-439 (2002-02-13)
There is evidence to suggest that rifampicin is an effective second line therapy for controlling pruritus in patients with chronic cholestatic liver disease. It is most widely used as an antipruritic agent in the autoimmune cholestatic liver disease, primary biliary...
Sandra V Kik et al.
The Journal of infectious diseases, 211 Suppl 2, S58-S66 (2015-03-15)
The potential available market (PAM) for new diagnostics for tuberculosis that meet the specifications of the high-priority target product profiles (TPPs) is currently unknown. We estimated the PAM in 2020 in 4 high-burden countries (South Africa, Brazil, China, and India)...
Daniela Baldoni et al.
Antimicrobial agents and chemotherapy, 53(3), 1142-1148 (2008-12-17)
We investigated the activity of linezolid, alone and in combination with rifampin (rifampicin), against a methicillin-resistant Staphylococcus aureus (MRSA) strain in vitro and in a guinea pig model of foreign-body infection. The MIC, minimal bactericidal concentration (MBC) in logarithmic phase...
Rodney Dawson et al.
Lancet (London, England), 385(9979), 1738-1747 (2015-03-22)
New antituberculosis regimens are urgently needed to shorten tuberculosis treatment. Following on from favourable assessment in a 2 week study, we investigated a novel regimen for efficacy and safety in drug-susceptible and multidrug-resistant (MDR) tuberculosis during the first 8 weeks...
Laurent Poirel et al.
Antimicrobial agents and chemotherapy, 55(2), 934-936 (2010-12-01)
Seven carbapenem-resistant NDM-1-positive Klebsiella pneumoniae isolates were recovered from patients hospitalized between 2007 and 2009 in different wards at a referral and tertiary care center in Nairobi. Most of the isolates were obtained from urine. All isolates carried the bla(NDM-1)...

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