Pet safety
Is Crown of Thornstoxic to cats & dogs?
Euphorbia milii
Quick verdict — at a glance
- Toxic to cats?
- Yes — toxic
- Toxic to dogs?
- Yes — toxic
- ASPCA classification
- Toxic to pets · botanical name Euphorbia milii
Is crown of thorns safe for cats and dogs?
Toxic — the ASPCA lists crown of thorns as a clear no for cats and dogs. The painful part for the pet is usually quick and intense; the right move is to keep it out of any room a pet roams unsupervised. This classification follows the ASPCA Toxic and Non-Toxic Plant List, the most widely used reference for companion-animal plant safety in the US and the standard most UK vets cite as well. Toxic to dogs and cats. The ASPCA and Pet Poison Helpline flag Euphorbia species (including E. milii) for their irritant milky latex sap, which contains diterpene/phorbol esters; ingestion causes drooling, mouth and gastrointestinal irritation, vomiting and diarrhoea, while sap contact irritates skin and eyes. The sharp thorns add a physical hazard. Keep away from pets and children and wear gloves when pruning.
| Pet | Toxic? | Per ASPCA |
|---|---|---|
| Cats | Yes | Toxic to pets |
| Dogs | Yes | Toxic to pets |
What happens if a pet eats crown of thorns?
Toxic to dogs and cats. The ASPCA and Pet Poison Helpline flag Euphorbia species (including E. milii) for their irritant milky latex sap, which contains diterpene/phorbol esters; ingestion causes drooling, mouth and gastrointestinal irritation, vomiting and diarrhoea, while sap contact irritates skin and eyes. The sharp thorns add a physical hazard. Keep away from pets and children and wear gloves when pruning. Signs usually appear soon after chewing rather than hours later. If you see drooling, pawing at the mouth, head-shaking, vomiting, loss of appetite, or unusual lethargy after your pet has had access to crown of thorns, treat it as a suspected ingestion and act on the steps below.
What to do if your pet ate crown of thorns
- Remove any plant material from your pet's mouth and move crown of thorns out of reach.
- Note how much was eaten and when, and watch for drooling, vomiting, or lethargy.
- Do not induce vomiting unless a vet or poison-control specialist instructs you to.
- Call your vet or the ASPCA Animal Poison Control Center on (888) 426-4435 and follow their advice.
- Bring a leaf or photo of crown of thorns to the appointment so it can be treated correctly.
This page is general guidance, not veterinary advice. Pets vary, and a reaction may be to soil, fertiliser, or pesticide rather than the plant. If you are worried, always contact a vet or the ASPCA Animal Poison Control Center on (888) 426-4435 — do not wait for symptoms to worsen.
Pet-safe alternatives to crown of thorns
Want the same look without the risk? These plants are listed as non-toxic to cats and dogs by the ASPCA and have similar care needs:
- Hoya — non-toxic to cats and dogs (care guide)
- Bromeliad — non-toxic to cats and dogs (care guide)
- Christmas cactus — non-toxic to cats and dogs (care guide)
- African violet — non-toxic to cats and dogs (care guide)
Crown of Thorns and pets — frequently asked questions
Is crown of thorns toxic to cats?
Crown of Thorns (Euphorbia milii) is toxic to pets to cats according to the ASPCA. Toxic to dogs and cats. The ASPCA and Pet Poison Helpline flag Euphorbia species (including E. milii) for their irritant milky latex sap, which contains diterpene/phorbol esters; ingestion causes drooling, mouth and gastrointestinal irritation, vomiting and diarrhoea, while sap contact irritates skin and eyes. The sharp thorns add a physical hazard. Keep away from pets and children and wear gloves when pruning. Keep it out of reach and contact your vet or the ASPCA Animal Poison Control Center on (888) 426-4435 if your cat chews it.
Is crown of thorns toxic to dogs?
The ASPCA lists the same toxicity status for dogs as for cats: Crown of Thorns is toxic to pets. Dogs often chew more enthusiastically than cats, so a toxic plant like crown of thorns is best removed from the floor and low shelves entirely.
What happens if my pet eats crown of thorns?
Toxic to dogs and cats. The ASPCA and Pet Poison Helpline flag Euphorbia species (including E. milii) for their irritant milky latex sap, which contains diterpene/phorbol esters; ingestion causes drooling, mouth and gastrointestinal irritation, vomiting and diarrhoea, while sap contact irritates skin and eyes. The sharp thorns add a physical hazard. Keep away from pets and children and wear gloves when pruning. Signs usually appear soon after chewing rather than hours later. If you see drooling, pawing at the mouth, head-shaking, vomiting, loss of appetite, or unusual lethargy after your pet has had access to crown of thorns, treat it as a suspected ingestion and act on the steps below.
What should I do if my cat or dog ate crown of thorns?
Stay calm. Remove any remaining plant material from your pet's mouth and take the plant away so they cannot eat more. Note roughly how much was eaten and when. Do not make your pet vomit unless a vet or poison-control specialist tells you to. Call your vet or the ASPCA Animal Poison Control Center on (888) 426-4435 (a consultation fee may apply) and follow their advice. Bringing a photo or a leaf of crown of thorns to the appointment helps the vet treat it correctly.
What are pet-safe alternatives to crown of thorns?
If you want a similar look without the risk, good non-toxic swaps include hoya, bromeliad, christmas cactus, african violet. All of these are listed as non-toxic to cats and dogs by the ASPCA, so they suit a home where pets have access to your plants.
Full crown of thorns care
Pet-safety is one piece of the picture. For light, watering, soil, and troubleshooting, see the complete crown of thorns care guide, or browse the full pet-safe plant library to check another plant before you buy it.