Virginia Creeper Poisoning in Dogs

The Virginia creeper vine is native to eastern and central North America. Its appearance is similar to poison ivy, but it has five leaflets rather than three on the mature vines. It is also used as a shading vine for masonry as it climbs by using disks on the plant, rather than by penetrating the masonry with its root system. All parts of the Virginia creeper contain the calcium oxalate crystals that cause irritation and pain that occurs when they are chewed or swallowed. The discomfort that is usually caused by the sharp crystals prevents most animals from doing more than sampling the plant material. Occasionally pets develop the urge to ingest large quantities of plant material. If that occurs, a visit to the veterinarian’s clinic may be required.

The Virginia creeper (Parthenocissus quinquefolia) contains insoluble calcium oxalate crystals which cause intense pain and irritation to the mouth and gastrointestinal system when chewed or swallowed.

The Virginia creeper vine contains insoluble calcium oxalate crystals in every part of the plant. When chewed or swallowed these crystals can cause numerous symptoms, including: 

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

Types

The Parthenocissus quinquefolia vine is native to eastern and central North America. Its appearance is similar to poison ivy, but it has five leaflets rather than three on the mature vines. Small, unobtrusive clusters of green flowers develop into dark purple berries which are an important food source for birds but contain additional oxalic acid which can be moderately toxic to  most mammals. Several other varieties of the plant also contain calcium oxalate crystals which cause the pain and irritation from the Virginia creeper. These plants can include: 

• Arrowhead vine (Syngonium podophyllum)
• Calla or arum lily (Zantedeschia aethiopica)
• 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)
• Rhubarb (Rheum rhabarbarum)
• Skunk cabbage (Symplocarpus foetidus)

All parts of the Virginia creeper contain the calcium oxalate crystals that can cause damage to the soft tissues. The irritant to the tissues is called calcium oxalate which is a calcium salt of oxalic acid. Chewing any part of the plant can result in intense swelling and pain to the mouth and throat as the tiny crystals known as raphides embed themselves deep into the soft tissues that they are introduced to. Swallowing the sap or plant material generally causes the inflammation to extend down through the throat and into the stomach, which can cause gastrointestinal discomfort and severe distress. Swelling of the throat has also been known to cause breathing difficulties if the airway becomes blocked. The berries also contain oxalic acid, which is known to cause additional gastrointestinal upset and can worsen symptoms.

Oral symptoms of exposure to the calcium oxalate crystals from the Virginia creeper will generally show up right away, although incomplete chewing during consumption can delay symptoms by up to two hours. Observable symptoms combined with the identification of the vine may be the only prerequisite for an initial diagnosis. If your dog does manage to ingest larger than average quantities of the vine or if you did not witness what your pet may have ingested, your veterinarian may advise that you and your pet visit their office. 

Your pet's doctor will ask you questions regarding any opportunistic eating that may have occurred of late. In addition, provide any information you may have about dietary supplements or prescriptions that are being concurrently administered to your pet. Tests to reveal if any concurrent diseases or disorders are present, such as a complete blood count, urinalysis, and biochemistry profiles, will be ordered at this time. If your dog’s exposure to the plant material is causing vomiting, then the vomit will also be examined and tested for toxins. Plant material discovered in the vomit may also be tested to confirm the preliminary diagnosis.

Preliminary treatment starts with a thorough rinsing out of the mouth and affected areas with clean, cold water to remove as many of the penetrating crystals as possible. The unpleasant taste and discomfort will usually inhibit the intake of substantial quantities of this vine for most mammals. In some cases, the rinsing of the mouth area may be all that is needed to treat the contamination, although something cool to eat or drink, such as ice chips or milk, may help to ease oral discomfort and inflammation until you are able to get further instructions from your veterinarian. 

If large volumes of the either the plant material or sap are ingested by your pet, a visit to the veterinarian’s office will be recommended. Dehydration will be prevented through the use of intravenous fluid treatments, and an antihistamine will be administered. If the airway is significantly swollen, your canine may need oxygen therapy which will require him to be kept under observation at the office until the swelling subsides. Gastroprotective medications may be suggested to prevent further damage to the lining of the stomach.

The prognosis for dogs that only consume small to moderate quantities of the plants containing the calcium oxalate crystals, such as the Virginia creeper, is usually good. Pain caused by the crystals in the mouth and gastrointestinal tract typically dissipates within just twelve to twenty-four hours from exposure. Swelling that occurs in the airway of the animal will need to be monitored and evaluated by a veterinarian. Significant exposures to the insoluble calcium oxalate crystals tend to be infrequent due to the nearly instantaneous swelling and pain to the mouth. Canines who do consume substantial amounts of the plants containing calcium oxalate, whether soluble or insoluble, are at risk for liver and kidney damage so monitoring of these vital organs may be endorsed in the event of the consumption of sizeable amounts. If you have questions as your pet recovers at home, do not hesitate to contact your veterinarian for advice.