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In the US, Fidaxomicin (fidaxomicin systemic) is a member of the drug class macrolides and is used to treat Clostridial Infection.

US matches:



ATC (Anatomical Therapeutic Chemical Classification)


CAS registry number (Chemical Abstracts Service)


Chemical Formula


Molecular Weight


Therapeutic Category

Antibacterial: Macrolide

Chemical Names

(3E,5E,8S,9E,11S,12R,13E,15E,18S)-3-{[(6-deoxy-4-O-(3,5-dichloro-2-etyl-4,6-dihydroxybenzoyl)-2-O-metyl-β-D-mannopyranosyl)oxy]metyl}-12-{[6-deoxy-5-C-metyl-4-O-(2-metylpropanoyl)-β-D-lyxo-hexopyranosyl]oxy}-11-etyl-8-hydroxy-18-[(1R)-1-hydroxyetyl]-9,13,15-trimetyloxacycloocta-3,5,9,13,15-pentaen-2-one (WHO)

Oxacyclooctadeca-3,5,9,13,15-pentaen-2-one, 3-[[[6-deoxy-4-O-(3,5-dichloro-2-etyl-4,6-dihydroxybenzoyl)-2-O-metyl-β-D-mannopyranosyl]oxy]metyl]-12[[6-deoxy-5-C-metyl-4-O-(2-metyl-1-oxopropyl)-β-D-lyxo-hexopyranosyl]oxy]-11-etyl-8-hydroxy-18-[(1R)-1-hydroxyetyl]-9,13,15-trimetyl-, (3E,5E,8S,9E,11S,12R,13E,15E,18S)- (CAS)

Foreign Names

  • Fidaxomicinum (Latin)
  • Fidaxomicin (German)
  • Fidaxomicine (French)
  • Fidaxomicina (Spanish)

Generic Names

  • Fidaxomicin (OS: USAN, BAN, JAN)
  • BRN 5228707 (IS)
  • Lipiarmycin (IS)
  • OPT-80 (IS)
  • PAR-101 (IS)
  • Tiacumicin B (IS)
  • UNII-Z5N076G8YQ (IS)

Brand Names

  • Dificid
    Cubist, United States; Merck Canada, Canada; Merck Sharp & Dohme, Australia; Pharmacy Retailing, New Zealand
  • Dificlir
    Astellas, Belgium; Astellas, Czech Republic; Astellas, Estonia; Astellas, Finland; Astellas, Georgia; Astellas, Ireland; Astellas, Romania; Astellas, Sweden; Astellas, Slovenia; Astellas, Slovakia; Astellas Pharma, Cyprus; Astellas Pharma, Germany; Astellas Pharma, United Kingdom; Astellas Pharma, Poland; Astellas Pharma Europe BV, Greece; Astellas, Spain; Astellas, France; Astellas, Iceland; Astellas, Lithuania; Astellas, Norway; Astellas Pharma, Denmark
  • Dificlir 200 mg
    Astellas, Hungary
  • Dificlir 200mg
    Abacus, Austria; Astellas, Switzerland; Astellas, Luxembourg; Astellas Pharma Europe, Austria


BANBritish Approved Name
CASChemical Abstracts Service
ISInofficial Synonym
JANJapanese Accepted Name
OSOfficial Synonym
Rec.INNRecommended International Nonproprietary Name (World Health Organization)
USANUnited States Adopted Name
WHOWorld Health Organization

Further information on drug naming conventions: International Nonproprietary Names.

Important Notice: The international database is in BETA release. This means it is still under development and may contain inaccuracies. It is not intended as a substitute for the expertise and judgement of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that the use of any medication in any country is safe, appropriate or effective for you. Consult with your healthcare professional before taking any medication.

Further information

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