Is Heartleaf Philodendron Toxic to Cats and Dogs?
The Heartleaf Philodendron is toxic to cats, dogs, and horses. Ingestion of any part of this plant can cause painful symptoms for pets.
The toxicity comes from a substance that causes immediate irritation to the mouth, lips, and tongue. While this discomfort often stops a pet from eating a large quantity, any amount of chewing or ingestion warrants caution and a potential call to your veterinarian.
Heartleaf Philodendron: what the ASPCA database lists
| ASPCA entry | Heartleaf Philodendron |
|---|---|
| Other common names | Cordatum, Sweetheart Plant |
| Scientific name | Philodendron hederaceum |
| Family | Araceae |
| Toxic to | Toxic to Dogs, Toxic to Cats, Toxic to Horses |
| Non-toxic to | None listed |
| Toxic principles | Insoluble calcium oxalates |
| Clinical signs listed | Oral irritation, pain and swelling of mouth, tongue and lips, excessive drooling, vomiting (not horses), difficulty swallowing |
Toxicity of Heartleaf Philodendron
The American Society for the Prevention of Cruelty to Animals (ASPCA) identifies the Heartleaf Philodendron, or Philodendron hederaceum, as toxic to cats, dogs, and horses. The plant contains insoluble calcium oxalates, which are the toxic principle.
When a pet chews or bites the plant, these crystal-like compounds are released and embed themselves in the soft tissues of the mouth and throat. This causes an immediate and painful reaction. The ASPCA lists the following clinical signs associated with philodendron poisoning:
- Oral irritation
- Pain and swelling of the mouth, tongue, and lips
- Excessive drooling
- Vomiting (not in horses)
- Difficulty swallowing
What This Means for Pet Owners
The presence of a Heartleaf Philodendron, also known as Cordatum or Sweetheart Plant, requires careful management in a home with pets. Curious animals, especially kittens and puppies, may be tempted to chew on its trailing vines and heart-shaped leaves. The pain from the calcium oxalate crystals is a strong deterrent, but even a small bite can lead to significant discomfort.
A pet experiencing these symptoms may paw at its mouth, refuse to eat, or show other signs of distress. The swelling can be a serious concern, particularly if it affects the pet’s ability to swallow. All parts of the plant are considered toxic. Homeowners should be mindful of fallen leaves or cuttings that a pet could find on the floor.
Keeping Pets and This Plant Apart
The safest way to have a Heartleaf Philodendron in a home with pets is to ensure the animals cannot access it. Place the plant on a very high shelf, in a hanging basket well out of reach, or in a room that is consistently closed off to pets. Supervise cats and dogs when they are in the same room as the plant. Be vigilant about cleaning up any leaves or stems that may drop from the plant during pruning or routine care.
Always check the labels of new plants you bring into your home. If you are unsure about a plant’s identity, it is best to keep it away from your pets until you can confirm it is safe. A slow and supervised introduction to any new object in their environment is a general best practice for pet owners.
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 see or suspect that your pet has chewed or eaten any part of a Heartleaf Philodendron, contact your veterinarian or the ASPCA Animal Poison Control Center at (888) 426-4435 immediately. A consultation fee may apply. Be prepared to share what part of the plant was ingested, how much, and when it happened.
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.