Published April 13, 2021 (current as of December 31, 2024)
A concerned veterinarian reported a potential risk with a medicine that is fatal to our furry family members, even after just licking their owners! The topical chemotherapy medicine, fluorouracil (Carac, Efudex, Fluoroplex), is a cream or solution that is often used to treat skin disorders such as actinic keratosis or basal cell carcinoma. But it is extremely toxic to dogs and cats. Despite receiving emergency veterinary treatment after coming into contact with fluorouracil, the rate of death within 24 hours is high for dogs and cats. Even when small amounts of fluorouracil are eaten or licked, the dog or cat can build up high levels of ammonia in their body, which can be deadly. The problem happens when a pet licks the owner’s skin where the medicine has been applied or chews the fluorouracil container or tube of medicine. Soon after this, the pet may vomit, have diarrhea, start shaking (tremors), become unsteady and fall over, and have seizures. Currently, nothing can be done to stop the effects of fluorouracil once it has been licked or eaten. Sadly, no warning label appears on fluorouracil products to alert pet owners about this risk. Please be sure to store fluorouracil products safely if pets (or children) are nearby, and to prevent dogs and cats from licking the owner’s skin if the cream or solution has been applied.
