Cats
Potentially toxicConsulted references classify the plant as toxic or irritating for that pet type.
Verified against ASPCA/provenance audit 2026-05-06 on May 6, 2026.

Heracleum maximum
Cow parsnip is a large, herbaceous perennial member of the carrot family known for its tall stature and umbrella-like flower clusters. It contains furanocoumarins that can cause significant skin and mucosal irritation upon contact.
Safety status
Cats
Potentially toxicConsulted references classify the plant as toxic or irritating for that pet type.
Verified against ASPCA/provenance audit 2026-05-06 on May 6, 2026.
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.
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.
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.
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.
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.
Sources: ASPCA.
If a pet has chewed or swallowed plant material and is showing symptoms, contact a veterinarian or poison resource immediately. This product is for structured reference, not diagnosis.
Cats — concern notes
Common signs
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.
Safer alternatives
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NC State Extension Plant Toolbox
botanical · 94% reliability
Heracleum maximum is a native perennial that can cause skin irritation in humans and animals due to furanocoumarins.
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