Philodendron Poisoning in Dogs

Philodendron is a large genus of tropical plant displaying large leaves in several shapes. Philodendrons are often used as a houseplant due to their low maintenance and interesting foliage. The insoluble calcium oxalate crystals are present in all parts of the Philodendron, and these crystals can cause extreme irritation and pain when the plant material is chewed or swallowed. The discomfort that is caused by the sharp crystals ordinarily prevents animals from doing more than tasting the plant. On rare occasions, your pet may end up swallowing larger amounts of plant material. If that occurs, your canine companion may need to visit the veterinarian’s office for an evaluation of symptoms.

All plants in the Philodendron genus contain calcium oxalate crystals which can cause intense swelling, pain, and irritation of the mouth and gastrointestinal tract when chewed or swallowed.

All philodendron plants contain insoluble calcium oxalate crystals throughout the plant. When chewed or swallowed these crystals can cause: 

• Cardiac arrhythmia
• Diarrhea
• Dilated eyes 
• Difficulty swallowing
• Excessive drooling
• Hoarse barking
• Labored breathing
• Loss of appetite
• Numbness of exposed area
• Obstruction of the airway
• Pawing/rubbing at the face or mouth
• Swelling of the tongue and lips
• Vocalization
• Vomiting

Types

Philodendron plants are most often encountered as houseplants as they are both attractive and low maintenance. Several other types of plants contain the same calcium oxalate crystals which are the cause of the pain and irritation from the philodendron variety of plants. These other plants can include: 

• Arrowhead vine (Syngonium podophyllum)
• Calla or arum lily (Zantedeschia aethiopica)
• Candelabra cactus (Euphorbia lactea)
• Chinese evergreen (Aglaonema modestrum)
• Devil’s ivy (Pothos, Epipremnum)
• Elephant’s ear (Alocasia/Caladium/Xanthosoma)
• Flamingo plant (Anthurium)
• Fruit salad plant (Monstera)
• Horsehead Philodendron (Philodendron bipennifolium)
• Jack-in-the-pulpit (Arisaema triphyllum)
• Peace lily (Spathiphyllum)
• Rhubarb (Rheum rhabarbarum)
• Skunk cabbage (Symplocarpus foetidus)
• Wild calla (Calla)

All parts of the philodendron contain the calcium oxalate crystals that can cause distress to your pet. Calcium oxalate is a calcium salt made of oxalic acid which generates irritation and then numbness in the tissues it comes into contact with. Chewing any part of the plant will cause immediate swelling and stinging pain to the mouth and throat areas of your dog as the tiny crystals embed themselves deep into the nearby soft tissues. If any of the sap or plant material is swallowed, the inflammation will usually extend down the throat and through the gastrointestinal tract. This can cause distress to your pet as well as severe internal pain. The swelling of the tongue and throat has also been known to cause breathing difficulties if the airway becomes blocked.

Symptoms are occasionally known to take up to two hours to show up, however, many symptoms of contact with the calcium oxalate crystals from consuming philodendron plants will be apparent right away, which means that identification of the plant in combination with your canine’s symptoms is often enough to allow for an initial diagnosis. If your dog chooses to ingest large quantities of plant material or if you did not observe what your pet may have ingested, your veterinarian may recommend a visit to the office.

Information will be collected from you regarding any opportunities for inappropriate grazing in addition to any dietary supplements or medicinal prescriptions that your dog is currently on. Tests, including a complete blood count, biochemistry profile, and urinalysis, may reveal any coexisting diseases or disorders when it is analyzed. If exposure to the plant material is causing your pet to vomit, then the vomitus will also be examined and tested for toxins. Plant material in the vomitus will be helpful in confirming the preliminary diagnosis.

Immediate treatment will generally begin with a thorough flushing out of the mouth and other affected areas with fresh, cold water. This is done to remove as many of the irritating crystals as possible. The unpleasant taste and discomfort will usually inhibit the intake of this plant by most dogs. This means that rinsing the mouth area may be all that is required, although your canine may also appreciate something cool to eat or drink, such as an ice cube or milk, to ease the oral discomfort until you are able to get further instructions from your veterinarian. Appropriate pain relievers or antihistamines may be recommended for your dog as well, depending on the circumstances. 

If large quantities of the either the plant material or sap were consumed, a visit to the veterinarian’s office would almost certainly be recommended. Intravenous fluid treatment will be offered to prevent dehydration, and if an antihistamine was not previously administered, administration as an intramuscular injection might occur at this time. In order to protect the stomach lining, gastroprotective medications may be administered to the patient. If the airway has become significantly swollen, your canine should be kept under observation at the veterinary office until the swelling has subsided.

Prognosis for dogs that ingest only smaller quantities of the plants containing the calcium oxalate crystals, such as the philodendron, is usually quite good. Pain caused by the crystals in the mouth and gastrointestinal tract is often displaced within just twelve to twenty-four hours after ingestion. Swelling in the airway needs be thoroughly evaluated and monitored by a veterinarian. Substantial doses of the plants that contain calcium oxalate crystals are rare due to the initial pain and discomfort in the mouth. Pets who do manage to consume significant amounts of these plants risk liver and kidney damage, so further monitoring of these organs would be warranted in the event of the ingestion of considerable quantities of the sap.