Octopus Tree Poisoning in Dogs

The octopus tree is a shrub or small tree with five to twelve glossy green leaves that radiate from each stalk. It is also commonly referred to as umbrella tree, Australian ivy palm, starleaf, and parasol plants; all parts of the octopus tree contain insoluble calcium oxalate crystals. These crystals cause intense pain and irritation to the mouth when chewed, and to the gastrointestinal system when swallowed. The irritation introduced by the sharp crystals as they embed themselves in your animal’s soft tissues most often prevents more than a sampling of the plant. In rare situations, your dog may swallow larger than average amounts of plant material. In that event, your canine companion may require a visit to your veterinarian’s office.

The octopus tree (Schefflera arboricola) contains insoluble calcium oxalate crystals which cause intense swelling and pain in the oral cavity and digestive system when chewed on or swallowed.

The octopus tree includes the  insoluble calcium oxalate crystals in all parts of the plant. When any part of these plants are chewed or swallowed these crystals can impart symptoms such as: 

• 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

The Schefflera arboricola is part of a widespread genus of small trees or shrubs with five to twelve green, glossy leaves that radiate from each stalk or branch. It is commonly called an octopus tree, but the schefflera shrub also goes by the names umbrella tree, parasol plant, and starleaf. Several other common plants also contain the insoluble calcium oxalate crystals that are known to cause this kind of distress when consumed. These plants can include: 

• Arrowhead vine (Syngonium podophyllum)
• Calla or arum lily (Zantedeschia aethiopica)
• Candelabra cactus (Euphorbia lactea)
• Charming Dieffenbachia (Dieffenbachia amoena
• Devil's ivy (Pothos, Epipremnum)
• Flamingo plant (Anthurium)
• Peace lily (Spathiphyllum)
• Philodendron (Philodendron)
• Rhubarb (Rheum rhabarbarum)
• Wild calla (Calla)

The entire octopus tree contains the insoluble calcium oxalate crystals that are the cause of the pain and discomfort. Calcium oxalate is a calcium salt of an oxalic acid which usually produces irritation and numbness in the soft tissues that it comes into contact with. Chewing any part of the plant generally triggers immediate pain in the mouth and throat as the microscopic crystals are embedded into each of the soft tissues that they come into contact with, followed by swelling and numbness. If the plant material or sap is swallowed, the irritation will extend down through the throat and the GI tract, causing severe pain as well as swelling. Swelling in the throat area can cause serious breathing difficulties if the airway becomes blocked.

Identification of the octopus tree, combined with the extreme rapidity of the onset of symptoms, is generally sufficient for an initial diagnosis. Occasionally, the symptoms will be delayed for up to two hours, especially if the plant material was swallowed with inadequate chewing. If your dog has consumed considerable quantities of the shrub, or if you are not certain about what your pet ingested, your veterinarian may recommend a visit to the office.

Your pet’s doctor will usually get the history of symptoms from you as well as getting any information regarding opportunities for inappropriate eating behavior in addition to any current supplements or prescriptions that your dog is taking to rule out other toxins, as well as conflicts with properly administered medications. A biochemistry profile, complete blood count (CBC), and urinalysis will be requested at this point as well. This will help to reveal any concurrent disorders or diseases that may be affecting your canine, as well as assist in evaluating the health and functioning of the vital organs.

Immediate treatment will begin with a thorough rinsing of the oral area with fresh, clean water to remove as many of the sharp crystals as possible. You may also want to offer your canine something else cold to eat or drink, such as ice cubes or even small amounts of milk. This will help to ease the pain and reduce the swelling until you are able to contact your veterinarian. The pain and discomfort caused by the crystals in the sap prevent most animals from consuming large quantities of the actual plant material, so the cleansing of the mouth area may be all that is required to give your pet some measure of relief. When this is not adequate to reduce the swelling and pain for your dog, your veterinarian may recommend an appropriate pain reliever or antihistamine as well, to reduce inflammation and suffering. 

If sizeable quantities of plant material or sap are consumed, a visit to the veterinarian’s office is generally needed. Once admitted, IV fluids will be offered to help your pet to combat dehydration and to balance the blood chemistry. If an antihistamine was not recommended prior to the visit, it might be administered at this time, as an intramuscular injection. Medications intended to protect the stomach lining may be suggested as well. If the airway is significantly impaired, the condition should be kept under observation at the veterinary hospital until the swelling subsides, and may require sedation and intubation.

The inflammatory effects of the crystals in the mouth and gastrointestinal tract are often dispelled within twelve to twenty-four hours from the most recent ingestion. Any subsequent swelling of the airway will need assessment by a veterinarian. Reports of substantial volumes of calcium oxalate crystals being ingested are atypical due to the initial pain and discomfort that occurs orally when the plant is chewed on, as well as the unpleasant taste, and the overall prognosis for dogs that are affected by small amounts of the plant that contain the calcium oxalate crystals, such as the octopus tree, is usually quite positive.  Higher volumes of consumption have occurred on occasion and they are known to impact the liver and kidneys. The liver and kidneys will require ongoing monitoring in the event of the ingestion of substantial quantities of the plant.