Heartleaf Philodendron

Yes, heartleaf philodendron (Philodendron hederaceum) is toxic to cats. It contains insoluble calcium oxalate crystals that cause immediate mechanical irritation to the mouth, tongue, and lips upon chewing.

Expect oral irritation, intense burning of the mouth and tongue, excessive drooling, pawing at the face, head shaking, vomiting, and difficulty swallowing. Visible swelling of the lips or tongue and changes in breathing are more serious signs that require immediate veterinary attention.

Remove any plant material from your cat's mouth and offer water to help rinse out the crystals. Monitor closely for swelling of the face or tongue, labored breathing, or an inability to swallow — call your vet or ASPCA Animal Poison Control at (888) 426-4435 immediately if any of those appear. Persistent drooling, vomiting, or refusal to eat for more than an hour also warrants a call.

Pain and drooling typically begin within minutes of chewing and most cats are noticeably better within 12–24 hours once supportive care is started, according to ASPCA records. Airway swelling is rare but can be life-threatening, so watch your cat closely during that window.

Yes, heartleaf philodendron (Philodendron hederaceum) is toxic to dogs. It contains insoluble calcium oxalate crystals that cause immediate oral irritation, intense burning of the mouth, tongue, and lips, excessive drooling, vomiting, and difficulty swallowing.

Signs typically appear within minutes of chewing and include pawing at the mouth, head shaking, foamy or excessive drooling, and lip-licking. This can progress to oral or tongue swelling, vomiting, and decreased appetite. Marked swelling that interferes with breathing is rare but possible.

Call your vet or the ASPCA Animal Poison Control Center at (888) 426-4435 immediately if you see visible swelling around the mouth, persistent drooling, repeated vomiting, or any change in breathing. Most dogs recover within 24 hours with supportive care, but professional guidance is warranted given the risk of airway swelling.

According to the ASPCA, no exact timing window is published, but irritation typically begins within minutes of chewing. Most dogs recover within 24 hours with supportive care; symptoms that persist beyond that or include swelling affecting breathing require prompt veterinary attention.