Is Monstera Toxic to Cats?

Last Updated on March 17, 2021 by Julia Wilson

Is monstera toxic to cats?

Monstera spp. is toxic to cats, the toxic principle is insoluble calcium oxalate crystals which are produced by specialised cells known as idioblasts and are a defensive mechanism against herbivory. Many plants contain calcium oxalate crystals which are arranged in bundles known as raphides. When a cat chews on the plant, needle-sharp needles penetrate the oropharynx causing acute pain and burning.

What is monstera?

  • Family: Araceae
  • Botanical name: Monstera spp.
  • Common names: Swiss cheese plant, Cheese plant, Mother-in-law, Fruit salad plant, Ceriman, Hurricane plant, Mexican breadfruit,
  • Toxicity: Toxic to cats
  • Toxic parts: All
  • Severity: Moderate
  • Toxic principle: Insoluble calcium oxalate crystals

Monstera spp. is a genus of 45 evergreen vines native to tropical regions of the Americas. Monstera delicosa (Swiss cheese plant) is the most well-known species popular as a houseplant.

The size of Monstera spp. leaves can range from a few cms to 60 cms or more. Many Monstera leaves develop splits or holes (known as fenestrations) as the leaves increase in size.

Popular monstera species include:

  • Monstera deliciosa – Swiss cheese plant
  • Monstera borsigiana – Monstera delicosa ‘wrinkle’
  • Monstera variegata – Variegated monstera delicosa
  • Monstera adansonii – Five holes plant
  • Monstera pinnatipartita -Monstera Pinnatipartita
  • Monstera dubia – Shingle plant
  • Monstera siltepecana – Silver monstera
  • Monstera obliqua – Swiss cheese vine
Monstera adansonii (Julia Wilson)

Cut-leaf philodendron, split-leaf philodendron and rhaphidophora tetrasperma are frequently referred to as monstera, in-fact the common name for rhaphidophora tetrasperma is ‘mini-monstera‘,  but none of these plants belongs to the monstera genus, although the toxic principle is the same.

Clinical signs

Most cats will stop chewing in response to the bitter taste and acute pain. Symptoms relate to acute oropharyngeal pain from contact with needle-shaped calcium oxalate crystals.

  • Oral pain and intense burning
  • Pawing at the mouth
  • Anorexia (loss of appetite)
  • Hypersalivation (drooling)
  • Soft tissue swelling
  • Vomiting
  • Difficulty swallowing
  • Swelling of the mouth and throat
  • Difficulty breathing (rare)

Although the response can look extreme to cat owners, symptoms are rarely life-threatening unless swelling develops, which can lead to breathing difficulty.

First aid

Give the cat a drink of something tasty such as milk, tuna juice or stock to flush the mouth. Watch for signs of swelling or difficulty breathing.


Contact your veterinarian or pet poison helpline for advice. They may recommend a wait and see approach. If the cat is experiencing difficulty breathing, seek immediate veterinary attention.

There is no specific antidote for monstera spp. ingestion and symptoms typically resolve quickly. Treatment is aimed at relieving symptoms and can include fluid therapy to correct dehydration and electrolyte imbalances due to vomiting, painkillers and manage airway obstructions in rare cases.


The only way to prevent Monstera toxicity is to not grow them in areas that cats can access. Some pet owners will find their cats pay no attention to the plants, but others, especially kittens may be prone to chewing on plants. There are plenty of cat-safe plants for animal lovers and green thumbs.

The good news is that in most cases signs are mild and usually limited to the oropharynx. However, plants, such as lilies and sago palm can be life-threatening to cats and should be avoided altogether.

Julia Wilson is a cat expert with over 20 years of experience writing about a wide range of cat topics, with a special interest in cat health, welfare and preventative care. Julia lives in Sydney with her family, four cats and two dogs. She enjoys photography, gardening and running in her spare time. Full author bio Contact Julia