Horsehead Philodendron in Dogs

The horsehead philodendron is a tropical plant displaying large lobed leaves. It is often used as a houseplant due to its low maintenance and interesting foliage. All parts of the horsehead philodendron contain insoluble calcium oxalate crystals and these crystals can cause extreme irritation and pain when chewed or swallowed. The discomfort that is caused by the sharp crystals usually 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 will most likely need to visit the veterinarian’s office.

The horsehead philodendron (Philodendron bipennifolium) contains calcium oxalate crystals which can cause intense pain and irritation in the mouth and gastrointestinal tract when chewed or swallowed.

The horsehead philodendron plant contains insoluble calcium oxalate crystals in all parts of the plant. When chewed or swallowed by your pet, these crystals can cause: 

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

Types

The Philodendron bipennifolium plant is most often found as a houseplant as it is both attractive and low maintenance. It most commonly called a horsehead philodendron but also goes by the names fiddle-leaf philodendron, fruit salad plant and panda plant. Several other types of plants contain the same calcium oxalate crystals which cause the pain and irritation from the horsehead philodendron These 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)
• Jack-in-the-pulpit (Arisaema triphyllum)
• Peace lily (Spathiphyllum)
• Philodendron (Philodendron)
• Rhubarb (Rheum rhabarbarum)
• Skunk cabbage (Symplocarpus foetidus)
• Wild calla (Calla)

All parts of the horsehead philodendron contain the calcium oxalate crystals that can cause distress to your pet. Calcium oxalate is a calcium salt of oxalic acid which produces irritation and numbness to the tissues it contacts. Chewing any part of the plant usually causes immediate swelling and stinging pain to the mouth and throat areas as the tiny crystals embed themselves deep into the soft tissues that they contact. If any of the sap or plant material is swallowed the inflammation can extend to the throat and down through the GI tract, causing distress and severe pain. The swelling has also been known to cause breathing difficulties if the airway becomes blocked.

Symptoms have occasionally taken up to two hours to show up, however, many possible symptoms of exposure to the calcium oxalate crystals from the horsehead philodendron will show up right away, so identification of the plant is often all that is required for diagnosing the cause of agony. If your dog does manage to ingest large quantities or if you did not observe what your pet may have ingested, your veterinarian may recommend a visit to their office. Information will be gathered from you regarding any opportunistic eating in addition to any concurrent supplements or prescriptions that your dog is on. Tests such as a complete blood count, biochemistry profile, and urinalysis will often reveal if any concurrent diseases or disorders are present. If your dog is vomiting from exposure to the plant material, then the vomitus will also be examined and tested for toxins. Plant material in the vomitus may also be tested to confirm the preliminary diagnosis.

Immediate treatment will start with a thorough rinsing out of the mouth and affected areas with clean and cool water 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 ingested a visit to the veterinarian’s office is generally recommended. IV fluid treatment will be offered to prevent dehydration, and if an antihistamine was not previously administered, administration as an intramuscular injection may occur at this time. Gastroprotective medications may be recommended to prevent damage to the stomach lining. If the airway is significantly swollen, your canine may need to be kept under observation at the office until the swelling subsides.

Prognosis for dogs that ingest only smaller quantities of the plants containing the calcium oxalate crystals, such as the horsehead philodendron, is usually quite good. Pain caused by the crystals in the mouth and gastrointestinal tract usually are usually displaced within just twelve to twenty-four hours from ingestion. Swelling in the airway will need to be evaluated and monitored by a veterinarian. Massive doses of calcium oxalate crystals are rare due to the initial pain and discomfort in the mouth. Pets who do manage to consume large amounts of these plants risk liver and kidney damage so further monitoring of these organs may be recommended in the event of the ingestion of substantial quantities of the sap.