Is hogweed & cow parsnip poisonous to pets?

Updated 2026-09-30 · 1 sources

Based on: NC State Extension Gardener Plant Toolbox

Call a vet today

Hogweed & cow parsnip are poisonous to dogs and cats – call your vet today for advice if your pet has eaten any of them. The plant's sap/juice is poisonous.

  • Dogs Call a vet today
  • Cats Call a vet today

What to do right now

  1. Call your vet or the nearest emergency vet.
  2. Note which plant, which part, how much and when.
  3. Take a photo or a piece of the plant with you.
  4. Remove what is left and move the plant out of reach.

Don't

  • Do not make your pet vomit unless a vet tells you to.
  • Do not give any human medicine.

Why it can be dangerous

Its sap can cause eye irritation, and exposure followed by sunlight is linked with photosensitization, including sunburn and dermatitis.[1] Hogweed & cow parsnip are listed as a problem for cats and dogs.[1]

Signs to watch for

  • Sunburn
  • Dermatitis
  • Eye irritation after exposure to sap

Signs may follow exposure to the sap and subsequent exposure to sunlight.

Scientific name
Heracleum
Poisonous parts
sap/juice
If your pet is struggling to breathe, has collapsed, is having a seizure or can't stand up: go to the nearest vet now.

Not sure how serious it is?

OkPaw asks a few quick questions about your pet and tells you in 30 seconds whether it can wait. Free on Google Play for Android.

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Common questions

Is hogweed & cow parsnip dangerous for cats too?

Yes. It is listed as a problem for cats and dogs. [1][1]

What signs can hogweed & cow parsnip cause?

The listed signs are photosensitization, including sunburn and dermatitis, and eye irritation after exposure to sap. [1][1]

Can the sap affect a pet's eyes?

The sap can cause eye irritation upon exposure. [1][1]

Sources

  1. NC State Extension Gardener Plant Toolbox

How this page was made: written with the help of AI from the sources below, then checked claim by claim against those sources. Urgency levels follow OkPaw’s fixed safety rules. It is guidance, not a diagnosis. How we write our pages

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