Houseplants That Are Toxic to Cats and Dogs (and Safe Alternatives)

A surprising number of extremely popular houseplants are toxic to cats and dogs to some degree — but "toxic" covers a wide range, from mild, self-limiting mouth irritation to genuine medical emergencies. Knowing the difference matters for making informed decisions about what to bring into a home with pets.

Mild Toxicity: Calcium Oxalate Plants

The single largest toxic category among houseplants is the arum family (Araceae) — pothos, philodendron, monstera, peace lily, dieffenbachia, ZZ plant, alocasia, and anthurium among them. These contain insoluble calcium oxalate crystals that cause immediate, painful irritation to the mouth and throat if chewed, along with drooling and vomiting. It's unpleasant but rarely life-threatening, and most pets stop chewing quickly because of the pain involved. Dieffenbachia in particular is nicknamed "dumb cane" for the temporary swelling and difficulty speaking (or in a pet's case, meowing or barking) it can cause in the mouth and throat.

Genuinely Serious: Sago Palm

Sago palm (Cycas revoluta) deserves to be singled out — this is not a mild-irritation plant. Every part contains a toxin called cycasin, with the seeds carrying the highest concentration, and the ASPCA Animal Poison Control Center has documented fatality rates of 50–75% in dogs that ingest it, from acute liver failure. If you have dogs, this species is worth avoiding entirely rather than simply keeping out of reach.

Cardiac Risk: Kalanchoe

Kalanchoe contains bufadienolides — cardiac glycosides in the same chemical class as digitalis. Most ingestions cause vomiting and diarrhea, but large amounts can affect heart rhythm. It's rarely fatal at typical ingestion amounts, but it's a step up from the more common calcium-oxalate irritation.

Other Notable Toxic Houseplants

• Aloe vera — toxic to cats and dogs (though the clear inner gel itself is considered edible); the compounds are concentrated in the yellow latex layer just under the skin.
• String of pearls — contains pyrrolizidine alkaloids, a genuinely more significant toxin than the mild oxalate irritation common to most other trailing houseplants.
• Jade plant — toxic to cats and dogs, though the exact toxic mechanism isn't fully identified; causes vomiting and incoordination.
• Snake plant — contains saponins; typically causes only mild vomiting or diarrhea.
• English ivy — leaves, berries, and sap are toxic to cats, dogs, and horses.

Genuinely Pet-Safe Popular Houseplants

If you'd rather sidestep the question entirely, plenty of popular species are confirmed non-toxic by the ASPCA:

• Spider plant
• Boston fern and bird's nest fern
• Calathea and prayer plant (Maranta)
• Parlor palm, areca palm, and ponytail palm
• African violet
• Peperomia (most species)
• Haworthia (zebra plant) and echeveria

What to Do If Your Pet Eats a Toxic Plant

Remove any remaining plant material from your pet's mouth if it's safe to do so, note which plant and roughly how much was eaten, and contact your veterinarian or the ASPCA Animal Poison Control Center. Don't wait to see if symptoms develop for anything beyond the mildest, most familiar irritant plants — and never induce vomiting unless a professional specifically tells you to.