Is Monstera Toxic to Cats?

Last Updated on October 27, 2021 by Julia Wilson

Is Monstera spp. toxic to cats?

Monstera spp. is toxic to cats, the toxic principle is insoluble calcium oxalate crystals which penetrate the oral mucosa causing acute pain and burning. Calcium oxalate crystals are produced by specialised cells known as idioblasts and are arranged in bundles known as raphides. They act as a defensive mechanism against herbivory.

What is Monstera spp.?

  • 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 deliciosa (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:

  • M. deliciosa – Swiss cheese plant
  • M. borsigiana – Monstera deliciosa ‘wrinkle’
  • M. variegata – Variegated monstera deliciosa
  • M. adansonii – Five holes plant
  • M. pinnatipartita -Monstera Pinnatipartita
  • M. dubia – Shingle plant
  • M. siltepecana – Silver monstera
  • M. 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-sharp 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.

What should I do if my cat eats Monstera?

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.

Treatment for Monstera ingestion in cats

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.

Prevention

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 them. 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 palms can be life-threatening to cats and must be avoided altogether.