Schefflera Poisoning in Dogs

The schefflera plant is a shrub or small tree with five to twelve glossy green leaves that radiate from each stalk. All parts of the schefflera shrub contain calcium oxalate crystals which are insoluble. These crystals can cause intense pain and irritation to the mouth as well as to the gastrointestinal system when chewed or swallowed. The irritation posed by the sharp crystals as they embed themselves in the soft tissues most often prevents animals from doing more than sampling the plant. In rare situations, the dog may swallow larger than average amounts of plant material. In that event, your canine companion should be evaluated by the veterinarian in order to provide relief from the pain as well as rule out complications of burning of tissues or breathing difficulties.

The schefflera plant (Schefflera arboricola) is one of many species that contain insoluble calcium oxalate crystals which can cause intense swelling and pain in the mouth and gastrointestinal tract when chewed on or swallowed.

The schefflera shrub contains insoluble calcium oxalate crystals throughout the plant. When any part of the plant is chewed or swallowed these crystals will 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

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

• Calla or arum lily (Zantedeschia aethiopica)
• Candelabra cactus (Euphorbia lactea)
• Charming Dieffenbachia (Dieffenbachia amoena)
• Chinese evergreen (Aglaonema modestrum)
• Elephant’s Ear (Alocasia/Caladium/Xanthosoma)
• Flamingo plant (Anthurium)
• Fruit salad plant (Monstera)
• Philodendron (Philodendron)
• Rhubarb (Rheum rhabarbarum)
• Skunk cabbage (Symplocarpus foetidus)
• Wild calla (Calla)

All parts of the schefflera shrub plant contain the calcium oxalate crystals that are the cause of any injury. Calcium oxalate is a calcium salt of an oxalic acid which produces a disconcerting irritation and numbness to the soft tissues that it comes into contact with. Chewing any part of the plant usually causes immediate pain in the mouth and throat as the minuscule crystals are embedded into any soft tissues that they contact, followed by numbness and swelling. If the sap or plant material is eaten, the irritation will extend down through the throat and the gastrointestinal tract, causing severe pain as well as swelling. Swelling in the throat area can cause breathing difficulties if the airway becomes blocked.

If you are not confident about what your pet has ingested, or if your dog has swallowed sizeable quantities of the schefflera shrub, your veterinarian will often recommend a visit to the office. Many of the signs of exposure to calcium oxalate crystals from the schefflera shrub become immediately apparent. Occasionally the symptoms will take up to two hours to develop, especially if the plant material was swallowed with inadequate chewing. Do not wait for symptoms to appear before heading to the clinic, in case swelling of the throat or tongue leads to an airway obstruction.

Your pet’s doctor will discuss the history of symptoms from you. If you feel your pet has had the  opportunity for a session of inappropriate eating, or if he has been given supplements or prescriptions in the past, the veterinarian will want to rule out alternate toxins or even conflicts with medication. A urinalysis, complete blood count, and biochemistry profile will be requested at this point as well, in order to reveal any concurrent disorders or diseases that may be affecting your canine. If the patient vomits after exposure to the plant material, then the vomit will also be examined and tested for toxins. Often, the presence of plant material that is found in the vomit may be helpful in confirming the diagnosis.

If you see you pet has eaten a portion of your schefflera plant, begin with a thorough dousing of the mouth and affected areas with clean, fresh water to remove as many of the pain inducing crystals as possible. You may also want to offer your canine something cold to eat or drink, such as ice cubes or even small quantities of milk, to ease the pain and reduce the swelling until you are able to contact your veterinarian. The unpleasant taste and discomfort caused by the sap will often prevent children and animals from consuming much actual plant material, so the cleansing of the mouth area may be all that is required to give your pet relief. In some situations, your veterinarian may also recommend giving your dog an appropriate pain reliever or antihistamine to reduce inflammation and suffering. 

If sizeable quantities of plant material or sap are consumed, a visit to the veterinarian’s office is necessary in order to provide pain relief and to verify that breathing passages are clear. Once admitted, intravenous fluid treatment will generally be offered to balance the blood chemistry and to  prevent dehydration. If an antihistamine was not administered prior to the visit, it might be given as an intramuscular injection at this time. Medications designed to protect the stomach lining may be recommended to prevent further damage. If the airway is significantly impaired, oxygen therapy will be given at the veterinary hospital until the swelling subsides.

The overall prognosis for dogs that are affected by small amounts of the plant that contains the calcium oxalate crystals, such as the schefflera shrub, is usually quite positive. The inflammatory effects of the crystals in the mouth and gastrointestinal tract typically disappear within twelve to twenty-four hours from the initial ingestion. Any subsequent swelling that occurs in the airway needs to be assessed 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. When larger doses have occurred, they are known to impact the liver and kidneys. This means that the liver and kidneys may need ongoing monitoring in the event of the ingestion of substantial quantities of the plant.