Is Hydrangea Toxic to Cats and Dogs? (Hydrangea arborescens)
Hydrangea, Hydrangea arborescens: listed as toxic to cats and dogs (cyanogenic glycoside). Signs, what to do, and how to confirm the species.
At a glance
- Scientific name: Hydrangea arborescens
- Also called: Hortensia, Hills of Snow, Seven Bark
- Toxic to cats: Yes
- Toxic to dogs: Yes
- Toxic principle: Cyanogenic glycoside
- Signs reported: Vomiting, depression, diarrhea. Cyanide intoxication is rare - usually produces more of a gastrointestinal disturbance.
Is Hydrangea toxic to cats and dogs?
ASPCA Animal Poison Control lists Hydrangea (Hydrangea arborescens) as toxic to cats and dogs. The toxic principle is Cyanogenic glycoside. Signs reported: Vomiting, depression, diarrhea. Cyanide intoxication is rare - usually produces more of a gastrointestinal disturbance..
How serious it can be
The original ASPCA text notes that cyanide poisoning is rare; most ingestions cause only gastrointestinal upset.
What to do if your pet ate it
If a pet may have eaten a plant, contact a veterinarian, ASPCA Animal Poison Control (888) 426-4435 or Pet Poison Helpline (855) 764-7661. Note what was eaten, how much and when, and bring a photo or a piece of the plant. Do not induce vomiting or give home remedies unless a professional tells you to.
Plants people check next
Confirm it is really this plant
Toxicity lists are by species, and many houseplants look alike. Photograph the whole plant, a leaf close-up and any flower in even light; the app reads the species first, then you can check it here. If the species is uncertain, act as if it were toxic.
FAQ
Is Hydrangea safe for cats?
No. It is listed as toxic to cats; reported signs include vomiting.
Is Hydrangea safe for dogs?
No. It is listed as toxic to dogs.
My pet only chewed a leaf. Should I still call?
Yes. Amount, size of the animal and the part eaten all matter, and the hotlines are staffed to judge that. Calling early is cheaper than waiting for signs.
Related
Sources
Updated 2026-09-11.