✕ Toxic

Oleander

Q: Is Oleander toxic to cats?

Warning: Toxic. Oleander (Nerium oleander) is an extremely dangerous and highly toxic plant for cats. Every single part of the plant is poisonous, including the leaves, flowers, stems, roots, and even dried pieces. The water in a vase holding oleander can also become toxic. The plant contains powerful chemicals called cardiac glycosides, such as oleandrin. These chemicals directly attack the heart's electrical system and muscle movements. Even a tiny amount, like a single leaf, can cause life-threatening heart problems for a cat. Symptoms can appear quickly and include drooling, vomiting, diarrhea, weakness, and severe breathing or heart issues. Because there is no safe amount of oleander, any exposure is highly dangerous. If you suspect your cat has chewed on or eaten any part of an oleander plant, please contact a veterinarian or an emergency animal hospital immediately—do not wait for symptoms to show.

Nerium oleander

Oleander (Nerium oleander) is an extremely dangerous and highly toxic plant for cats. Every single part of the plant is poisonous, including the leaves, flowers, stems, roots, and even dried pieces. The water in a vase holding oleander can also become toxic. The plant contains powerful chemicals called cardiac glycosides, such as oleandrin. These chemicals directly attack the heart's electrical system and muscle movements. Even a tiny amount, like a single leaf, can cause life-threatening heart problems for a cat. Symptoms can appear quickly and include drooling, vomiting, diarrhea, weakness, and severe breathing or heart issues. Because there is no safe amount of oleander, any exposure is highly dangerous. If you suspect your cat has chewed on or eaten any part of an oleander plant, please contact a veterinarian or an emergency animal hospital immediately—do not wait for symptoms to show.

Important Notes

Toxic compounds: oleandrin and neriine (cardenolide cardiac glycosides); all parts are toxic, including dried material and smoke from burning

Mechanism: cardenolides inhibit Na+/K+-ATPase in cardiac muscle, disrupting electrical conduction and causing arrhythmias and heart block

Symptoms: drooling, vomiting, diarrhea, weakness, bradycardia, cardiac arrhythmias, hypotension, collapse; can be rapidly fatal

A single leaf contains enough oleandrin to kill a cat; smoke from burning oleander is also toxic

Any suspected ingestion is a veterinary emergency — do not wait for symptoms

Potentially Toxic Parts

Leaf

Entire Plant

Possible Symptoms Reported in Cats

Irregular heart rhythms (arrhythmias), abnormally slow heart rate (bradycardia) or fast heart rate (tachycardia), and low blood pressure (hypotension)

Cardiac · Within the first 2 hours after exposure,

Drooling (hypersalivation), nausea, vomiting, diarrhea, and abdominal pain

Gastrointestinal · Rapidly, usually within the first 2 hours after exposure,

Lethargy, profound weakness, drowsiness, muscle tremors, seizures, and a lack of consciousness

Gastrointestinal · Manifests quickly, within the first 2 hours as the systemic toxicity progresses15. • Any additional

Difficulty breathing and respiratory changes

Respiratory · Manifests rapidly as the toxicity progresses1. • Any additional

Disclaimer: This summary was compiled from multiple sources and is for informational use only. It is not a diagnosis or treatment plan. Toxicity can vary based on the substance, amount, plant part, and individual cat. If you think your cat may have been exposed to a toxic substance, contact a veterinarian right away.