Is Oleander Toxic to Cats and Dogs?
Yes, oleander is toxic to both cats and dogs. The American Society for the Prevention of Cruelty to Animals (ASPCA) includes this plant in its database of toxic plants because it contains substances called cardiac glycosides.
Every part of the oleander plant is considered dangerous to pets if ingested, including the leaves, stems, flowers, and even the water from a vase holding its cuttings. Due to its severe toxicity, pet owners should be extremely cautious with this plant.
Oleander: what the ASPCA database lists
| ASPCA entry | Oleander |
|---|---|
| Other common names | Rose-Bay |
| Scientific name | Nerium oleander |
| Family | Apocynaceae |
| Toxic to | Toxic to Dogs, Toxic to Cats, Toxic to Horses |
| Non-toxic to | None listed |
| Toxic principles | Cardiac glycosides |
| Clinical signs listed | Drooling, abdominal pain, diarrhea, colic, depression, death |
What the ASPCA lists for oleander
The ASPCA identifies oleander, also known as Rose-Bay (Nerium oleander), as a member of the Apocynaceae family. It is officially listed as toxic to cats, dogs, and horses.
The toxicity comes from its cardiac glycosides. The ASPCA notes several clinical signs that can occur after a pet ingests any part of the plant. These signs may include:
- Drooling
- Abdominal pain
- Diarrhea
- Colic
- Depression
In severe cases, ingestion can lead to death. The presence of any of these signs warrants immediate veterinary attention.
What oleander toxicity means in a home with pets
The toxic compounds in oleander, cardiac glycosides, can seriously affect an animal’s heart function and gastrointestinal system. Because every part of the plant is poisonous, even a small amount can be harmful. A curious dog might chew on a fallen leaf or stick, while a cat could nibble on a flower or lick pollen from its fur. Pets should also be prevented from drinking water from a vase or dish that has contained oleander cuttings, as the toxins can leach into the water.
The list of clinical signs from the ASPCA, ranging from drooling and abdominal pain to depression, shows that the effects are systemic and serious. The potential for death underscores the importance of preventing any and all contact between pets and this plant.
Keeping cats and dogs and this plant apart
Given the severe toxicity of oleander, the safest approach for pet owners is to not have this plant in their home or in accessible garden areas. If the plant is in a neighbor’s yard, ensure your pet cannot access it.
Always supervise pets when they are outdoors in unfenced spaces. For indoor arrangements, it is best to choose plants known to be non-toxic to cats and dogs. If you receive a floral bouquet, inspect it carefully and remove any oleander before bringing it into your home. Keep all plant materials, including dried leaves and fallen flowers, swept up and disposed of in a secure bin that pets cannot open.
When to call your vet
If your pet chewed or ate part of this plant, call your veterinarian or an animal poison control line. Note which plant and which part, how much may be gone and when, and take a photo or a piece of the plant with you.
If you suspect your cat or dog has chewed on or eaten any part of an oleander plant, contact your veterinarian or the ASPCA Animal Poison Control Center at (888) 426-4435 immediately. Do not wait for symptoms to appear. Be prepared to share what part of the plant was eaten, how much, and when the exposure occurred.
Emergency signs: go now
- Collapse, fainting or severe weakness
- Seizures, tremors or trouble standing
- Trouble breathing or blue, gray or very pale gums
- Repeated vomiting or retching, or a swollen, painful belly
- Any known contact with a substance listed as toxic, even before signs appear
Book an appointment soon
- Vomiting or diarrhea that lasts or keeps coming back
- Not eating or drinking, or drinking much more than usual
- Drooling, pawing at the mouth or a swollen face
- Lethargy, hiding or acting unlike themselves
ASPCA Animal Poison Control Center: (888) 426-4435 (a consultation fee may apply). Your own vet or nearest emergency clinic is always a good first call.
Sources
Last checked October 21, 2026. Listings and guidance can change; your veterinarian knows your pet’s health history.