All plants › Cats › Crown of Thorns

Is Crown of Thorns Toxic to Cats?

☠️ ToxicSeverity: Mild
✅ Cross-checked against veterinary poison-control guidance · Oct 2026 audit
⚠️ Educational info only. If your pet just chewed something and looks unwell, skip the reading and call your vet or Pet Poison Helpline (US): (855) 764-7661.
Yes, crown of thorns is toxic to cats. The white sap is a Euphorbia latex that burns the mouth and stomach, and the thorns add a physical hazard.

Also known as: Euphorbia milii, Christ Plant, Christ Thorn · Euphorbia milii

What makes it toxic

Diterpene ester-containing milky latex in stems and leaves. The sap is caustic to mucous membranes and skin; thorns can wound a pawing cat and introduce sap into the wound.

Warning signs to watch for

Drooling, mouth irritation, vomiting and pawing at the face within minutes; skin contact causes redness and blistering in sensitive animals.

What to do if your cat eats it

Rinse the mouth and any exposed skin with water, remove plant material and offer water. Call your vet if vomiting persists or skin blisters appear.

Common questions

Is crown of thorns as dangerous as poinsettia?

Both are Euphorbias with irritating latex; crown of thorns sap is comparable or slightly stronger, and its thorns add injury risk. Keep it off cat-accessible windowsills.

My cat swatted it and a thorn stuck in her paw — anything special to do?

Remove the thorn, wash the site and watch for swelling — sap in a puncture wound irritates more. See the vet if the paw becomes hot or the cat limps beyond a day.

More plants checked for cats

Pothos☠️ ToxicYes, pothos is toxic to cats. Chewing the leaves or vines releases sharp calcium oxalate crystalAloe Vera⚠️ Mildly ToxicAloe vera is mildly to moderately toxic to cats. The gel is famously soothing for human skin, buSpider Plant✅ Non-ToxicNo, spider plants are non-toxic to cats. They are one of the best houseplants for homes with curEaster Lily☠️ ToxicYes — and this is one of the most dangerous plants a cat can meet. Every part of an Easter lily,Sago Palm☠️ ToxicYes — sago palm is severely toxic to cats and among the deadliest houseplants. Every part contaiBoston Fern✅ Non-ToxicNo, Boston ferns are non-toxic to cats — a classic choice for plant-loving cat households.

This page is general educational information, not a substitute for professional veterinary advice. Every pet is different — if your animal ate something concerning, contact your veterinarian or a pet poison hotline right away. Checking what your pet can eat? Visit our sister site SafeOrToxic.