Is Oleander Toxic to Cats?
Also known as: Nerium, Rose Bay, Nerium oleander · Nerium oleander
What makes it toxic
Cardiac glycosides, chiefly oleandrin and neriine, throughout the plant including flowers, leaves, stems, roots and nectar. They disrupt the heart’s electrical system the way digoxin does.
Warning signs to watch for
Drooling, vomiting and diarrhea, sometimes with blood, within hours; then weakness, slow or irregular heartbeat, dilated pupils, tremors, seizures and collapse.
What to do if your cat eats it
This is a drop-everything emergency. Go straight to a vet or animal ER, bringing a plant sample. Early decontamination and continuous heart monitoring are the only real chance in significant ingestions.
Common questions
Can a single leaf of oleander kill a cat?
It is genuinely possible. Oleandrin is extremely potent, and a cat’s body weight leaves almost no margin — treat any contact as an emergency.
Is it dangerous to burn oleander trimmings?
Yes. Smoke carries the glycosides, so never burn prunings where pets or people breathe the fumes, and never use them as mulch or compost.
Do the pretty flowers carry the same poison?
Yes — all parts, including nectar. There is no safe part of an oleander for any animal.
More plants checked for cats
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.