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Is Oleander Toxic to Dogs?

☠️ ToxicSeverity: Severe
✅ 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 — oleander is severely toxic to dogs. Even a few leaves can trigger vomiting and fatal heart rhythm failure.

Also known as: Nerium, Rose Bay, Nerium oleander · Nerium oleander

What makes it toxic

Oleandrin and related cardiac glycosides in every tissue of the plant. They poison the sodium-potassium pump in heart cells, producing life-threatening arrhythmias.

Warning signs to watch for

Drooling, vomiting and bloody diarrhea within hours, followed by lethargy, a slow irregular pulse, dilated pupils, wobbliness, tremors, seizures and death without treatment.

What to do if your dog eats it

This is an immediate ER emergency. Take the dog to a vet or animal hospital now, with a sample of the plant. Do not wait for symptoms — by the time the heart slows, treatment is critical.

Common questions

How little oleander is dangerous to a dog?

A surprisingly small amount — a mouthful of leaves has seriously poisoned dogs. There is no dose worth gambling on.

My dog only chewed a stick in the yard — is that serious?

Yes, contact the vet immediately anyway. Twigs, dead leaves and dried plant matter all retain oleandrin.

Is oleander used as medicine, so is a little safe?

The drug digoxin comes from a related glycoside class and is dosed precisely by professionals. Raw oleander is unpredictable and deadly — never treat it as a doseable herb.

More plants checked for dogs

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.