Safety verdict
Consulted references classify the plant as toxic or irritating for that pet type.
Pet ingestion lookup
My cat ate Cow Parsnip - what should I do?
Heracleum maximum
Potentially toxic
Contact your veterinarian or an animal poison-control resource now, especially if any amount was chewed or swallowed.
Verified against ASPCA/provenance audit 2026-05-06 on May 6, 2026.
Signs to watch for
Dermatitis, blistering, redness, and irritation of the mouth or throat if ingested.
Escalation note
The plant contains photosensitizing compounds that can cause severe skin reactions when exposed to sunlight. Please contact your veterinarian if you suspect ingestion or skin contact.
First aid at home
Move the cat indoors and out of direct sunlight. With gloves on, wipe sap off the fur with a damp cloth and rinse the mouth gently with cool water if the cat will tolerate it. Do not induce vomiting. Then call your vet or ASPCA Animal Poison Control at (888) 426-4435.
What to watch for
Mouth and tongue irritation if leaves were chewed; redness, blistering, or hair loss on areas the sap contacted (often muzzle, paws, and ears); pawing at the face; squinting or eye irritation. Skin reactions worsen sharply once the cat goes into sunlight.
Time window
Skin reactions appear once the contact area meets UV light — usually within 24–48 hours of exposure — and can take days to a week or more to resolve. Oral irritation typically settles within a day if the cat stops chewing.
When to call the vet
Call any time you see blistering, raw skin, eye irritation, persistent drooling, or refusal to eat. Cats are small and skin reactions can become severe with normal sun exposure, so don't wait to see if it worsens.
What this means for your cat
Cats — toxic. ASPCA classifies cow parsnip as toxic to cats; the furanocoumarins in the foliage cause phytophotodermatitis, a sun-triggered chemical burn that flares wherever sap touches skin or fur. Cats that brush past stems and then groom themselves can spread the sap across paws, muzzle, and ears.
Sources: ASPCA.
Poison-control resources
This page summarizes source-bound plant-safety information and is not veterinary advice.