Fenthion is potent cholinesterase inhibitor used as an insecticide and acaricide.
Fenthion is an organothiophosphorus compound used topically. In cattle it is used as dust or spray to control grubs, and in dogs as a spot dermal application that is effective against fleas for 2 to 3 weeks. 1,2
This drug should not be used simultaneously or within a few days or before or after treatment with cholinesterase-inhibiting drugs, pesticides or chemicals. 3
Fenthion is not used on puppies under 10 weeks of age, sick, stressed or convalescing dogs. Safe use in breeding males has not been established. 5
Fenthion is very toxic to birds, where it has been used as a perch toxicant; extremely toxic to poultry. Topical treatment is very toxic to young kittens. In dogs, side effects include tremor, vomiting, salivation, diarrhea, and weakness in puppies and older dogs, from overdosing. 4
REF FILE 324-DAC