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Fluorouracil
Toxic doses for cat from published sources; they are not treatment doses.
Toxic doses
Single acute ingestion, mg of the substance per kg of body weight. These are toxic doses, not treatment doses.
| Species | Signs begin | Severe | Deaths reported | Source |
|---|---|---|---|---|
|
Cat
also gels and creams licked off |
not established | not established | not established |
Saba et al. 2013 · Harvey et al. 1977 +1
Medium confidence
Reports and an experimental study (Harvey et al. 1977; Okeda et al. 1988); its use in cats has long been discouraged (Saba et al. 2013). Scientific article A study or review published in a scientific journal. Its findings apply to the animals and conditions it studied. Veterinary and Comparative Oncology, Vet Comp Oncol 2013;11(4):265-271, 2013 use of 5-FU in cats discouraged because of neurotoxicity and death Scientific article A study or review published in a scientific journal. Its findings apply to the animals and conditions it studied. Journal of the American Veterinary Medical Association, J Am Vet Med Assoc 1977;171(3):277-278, 1977 neurotoxicosis with 5-FU in five dogs and one cat Scientific article A study or review published in a scientific journal. Its findings apply to the animals and conditions it studied. Acta Pathologica Japonica, Acta Pathol Jpn 1988;38(10):1255-1266, 1988 2 mg/kg/day oral 5-FU: brain vacuolation and softening in cats |
Cat
Signs: Neurological signs (hyperexcitability, tremors, ataxia, seizures), vomiting; death.
5-fluorouracil (5-FU) is avoided in cats because of neurotoxicity and death. The usual exposure is a human 5% skin cream: a chewed tube, or licking skin treated with it. In a study, 2 mg/kg a day by mouth caused brain lesions in cats. No safe dose for cats is established.
Safety information
Known Contraindications
-
Critical
(Cat) Do not use 5-fluorouracil in cats by any route: neurotoxicity and death. Keep human 5-FU skin creams away from cats and from skin they may lick.
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