Cutleaf Philodendron Poisoning in Cats

Cutleaf philodendrons have large, glossy, split leaves with oblong holes. This plant is known for producing a delicious fruit, which looks like green corn cobs and are edible. However, the rest of the plant is poisonous, and unripe fruit causes irritation of the mouth and gastrointestinal tract. Cutleaf philodendrons pose a danger of poisoning to cats as they are often kept as houseplants or, less commonly, in tropical regions, they are kept in the garden where they are cultivated for their fruit. As they pose a real danger to cats, a cat that has accidentally ingested cutleaf philodendron should receive veterinary attention immediately.

The cutleaf philodendron is a vine native to the rainforests of Mexico and Panama that is poisonous to cats. It can be confusing, as it has multiple common and botanical names. Botanical names include Monstera deliciosa and Philodendron pertusum, and common names include hurricane plant, Swiss cheese plant, Mexican breadfruit, window leaf plant, split leaf Philodendron, ceriman and taro vine. 

The primary symptom of Cutleaf Philodendron poisoning is oral irritation. Symptoms usually occur immediately to two hours of ingestion and can continue for up to two weeks after ingestion of the plant. Symptoms include:

• Burning of mouth, tongue and lips
• Drooling
• Vomiting
• Difficulty swallowing (dysphagia)
• Choking
• Pain
• Pawing at the mouth
• Distorted vocalization
• Diarrhea due to irritation of the stomach
• Loss of appetite

Ingestion in large quantities can result in severe poisoning symptoms, including:

• Severe digestive disorder
• Difficulty breathing due to swelling of the throat
• Convulsions
• Renal failure
• Liver failure
• Cardiac abnormalities
• Dilated pupils
• Coma
• Death

Cutleaf philodendrons contain an insoluble non-living substance called calcium oxalate. 

Calcium oxalate is a needlelike crystal that is sharp at one end and contained in a gelatinous substance in the plant. When your cat ingests the leaves or other parts of the plant, the breaking down of the material causes the needle-like calcium oxalate crystal to be released and embed themselves in oral and gastrointestinal tissues. This causes immediate discomfort as needle-like structures of calcium oxalate are embedded in the mouth, tongue, and throat. This process may continue for some time after ingestion, allowing crystal oxalate “needles” to become embedded in the stomach and intestine and causing gastrointestinal distress. 

Because the plant parts of cutleaf philodendron are unpleasant tasting and bitter, it is unlikely that a cat will choose to ingest large amounts of this plant, and effects are usually restricted to irritation of the mouth. However, if large amounts are ingested, gastrointestinal upset can lead to dehydration and electrolyte imbalance due to vomiting and diarrhea.

If you suspect your cat of ingesting cutleaf philodendron or any other plant that is followed by symptoms of poisoning, take a sample of the plant with you to the veterinarian. This will greatly aid your veterinarian in determining the cause of the poisoning and administering the appropriate treatment. Upon presentation of a cat with symptoms of plant poisoning, your veterinarian will perform a complete physical medical examination, taking note of your cat’s vital signs and ordering appropriate tests. Blood, urinalysis, and radiographs such as x rays and ultrasounds may be ordered to rule out other causes of symptoms, and determine the extent of damage that the ingested toxic substance has caused. Severe symptoms, such as signs of electrolyte imbalance or damage to kidneys may show up on routine tests which will help your veterinarian determine appropriate treatment.

Your veterinarian will flush out your cat's oral cavity and provide medication that will coat remaining needles, such as Kapectolin.

If vomiting and diarrhea have occurred and your cat is dehydrated, treatment with intravenous fluids will be provided. If a large enough amount has been ingested and has caused breathing problems, respiratory assistance in the form of oxygen therapy will be provided.

Antihistamines may be administered orally if possible, or by intramuscular injection, if oral cavity is sufficiently irritated so as not to allow oral administration. This will reduce your cat’s reaction and swelling caused by the calcium oxalate crystals. 

Medication such as Sucralfate may be administered, orally if possible, which forms a paste when it reacts with stomach acid. This paste will create a barrier between the stomach and its contents, preventing the embedding of more calcium oxalate “needles” in the gastrointestinal tract. 

If swelling interferes with your cat’s ability to breathe, your cat will be hospitalized and monitored until normal breathing is restored. 

If a small amount of cutleaf philodendron is ingested and treatment by a veterinarian received in a timely fashion, your cat should recover in a few days. As symptoms can continue for many days post-ingestion, your cat should be monitored to ensure that all symptoms have been addressed. 

If a large amount of the plant was ingested resulting in severe calcium oxalate poisoning, permanent damage to vital organs such as the liver and kidney may have occurred and prognosis is guarded in these cases. 

The cutleaf philodendron plant should be removed from your cat's environment, whether in the home or garden. A special diet, as directed by your veterinarian, to prevent further embedding of needles and further irritation to your cat's gastrointestinal tract should be given. Rest and careful monitoring should be provided until your cat has recovered in a few weeks.