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In some countries, this medicine may only be approved for veterinary use.


BP vet.

CAS registry number (Chemical Abstracts Service)


Chemical Formula


Molecular Weight


Therapeutic Categories



Chemical Names

Dimetoxy-[3-metyl-4-(metyltio)phenoxy]-tioxophosphorane (IUPAC)

O,O-Dimetyl O-(3-metyl-4-metyltiophenyl)phosphorotioate

O,O-dimetyl O-(4-metylmercapto-3-metylphenyl) tionophosphate

O,O-dimetyl O-4-metyltio-m-tolylphosphorotioate (BP vet.)

Phosphorotioic acid, O,O-dimetyl O-[3-metyl-4-(metyltio)phenyl] ester

Foreign Names

  • Fenthionum (Latin)
  • Fenthion (German)
  • Fenthion (French)
  • Fentión (Spanish)

Generic Names

  • Fenthion (OS: BAN, DCF)
  • Bayer-29493 (IS)
  • CCRIS 310 (IS)
  • ENT-25540 (IS)
  • Mercaptophos (IS)
  • OMS 2 (IS)
  • S-1752 (IS)
  • Fenthion (PH: BP vet. 2015)

Brand Names

  • Bayopet (veterinary use)
    Bayer AH, South Africa
  • Pro-Spot (veterinary use)
    Bayer Animal Health, United States
  • Spotton 20% (veterinary use)
    Bayer Animal Health, United States
  • Tiguvon (veterinary use)
    Bayer Animal Health, United States; Bayer Australia Ltd Animal Health, Australia


BANBritish Approved Name
BP vet.British Pharmacopoeia (vet)
DCFDénomination Commune Française
IUPACInternational Union of Pure and Applied Chemistry
ISInofficial Synonym
OSOfficial Synonym
PHPharmacopoeia Name

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

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