Leather Flower Poisoning in Dogs

Vines in the clematis genus are also referred to as virgin’s bower and old man’s beard. The clematis genus belongs in the buttercup family Ranunculaceae, and like other plants in the Ranunculaceae, all parts of the clematis plants contain various cardiac glycosides as well as ranunculin, a glucoside which breaks down into the toxin protoanemonin in the digestive system. Collectively, these compounds can cause symptoms from drooling to neurological and cardiac disturbances. Fortunately, this plant is quite unpalatable, making severe poisonings especially rare.

Leather flower vine refers to one of 300 or so climbing vines with woody stems in the clematis genus. This vine contains several compounds that render it moderately toxic.

In most cases, very little of the plant material is actually ingested, and the symptoms remain mild. Substantial amounts of the plant would be required for major toxicity to develop and, in most cases, not enough material is ingested to trigger the more alarming of the possible symptoms. Symptoms caused by protoanemonin ingestion can include:

• Abdominal pain
• Blistering of the mouth and throat
• Bloody or tarry stools
• Difficulty chewing
• Dizziness
• Diarrhea
• Excessive drooling
• Hepatitis
• Jaundice
• Nausea
• Pawing at mouth
• Spasms
• Vomiting

Glycoside toxicity involves the cardiac and central nervous systems and can add symptoms like: 

• Abnormal heart rate
• Cardiac arrhythmias
• Collapse
• Confusion
• Depression
• Dilated pupils
• Disorientation
• Lethargy
• Seizures
• Sudden death
• Tremors
• Weakness

Types 

Leather flower can refer to the entire clematis genus, although certain species, especially those with thick or fleshy flowers, are more likely to go by this moniker than others. Some of the varieties that commonly use this title include:

• Clematis addisonii- Addison’s leather flower
• Clematis albicoma- Whitehair leather flower
• Clematis coactilis-  Virginia white-hair leatherflower
• Clematis crispa- Swamp leatherflower
• Clematis fremontii- Fremont’s leather flower
• Clematis glaucophylla- Whiteleaf leather flower
• Clematis morefieldii- Morefield’s leather flower
• Clematis reticulata- Netleaf leather flower
• Clematis socialis- Alabama leather flower
• Clematis texensis- Scarlet leather flower
• Clematis versicolor- Pale leather flower
• Clematis viticaulis- Millboro leather flower
• Clematis viticella- Italian leather flower

There are two categories of toxin at work with the leather flower vine; cardiac glycosides which are found in several plant families, and a glucoside called ranunculin found exclusively in plants in the buttercup family. The ranunculin breaks down into the toxin protoanemonin as it decomposes, and it decomposes rapidly when the plant is damaged. This toxin is responsible for the pain and blistering that occurs when the plant is first ingested, and if substantial amounts are ingested, bleeding in the digestive tract. 

The glycosides, on the other hand, affect the cardiac and central nervous systems. It is somewhat rare for the glycosides in the leather flower vine to have an effect, as the unpleasant taste, the pain, and the burning tends to discourage most animals from eating substantial enough quantities to cause symptoms to develop.

When consumption of the leather flower is witnessed, then the primary diagnosis will be based on the symptoms showing, along with the identification of the plant. Reactions to these plants are generally relatively mild unless large volumes of the plant are eaten. If the symptoms become severe, a sample of the plant should be brought with you to the veterinarian’s office if possible, in order to confirm the identification of the plant. If the signs and symptoms are incongruent with clematis poisoning, or if the eating of the plant was unwitnessed, then the diagnostic procedure may be more involved. Your veterinarian will generally order a biochemistry profile, complete blood count, and urinalysis when you visit the clinic, with an emphasis on heart rhythm and function. 

A history of your pet’s health will also be needed, as well as information regarding any medications or supplements being administered to your pet.  Drugs such as steroids, beta-blockers, and some chemotherapy agents may interact negatively with the cardiac glycosides present in the clematis genus of plants. Tests to check the functionality of the kidneys and the liver are also helpful in determining if any impairment has occurred with either organ.

Prognosis will be dependent how much was consumed, the size of the patient, and what symptoms are being exhibited. The first order of business should be a thorough rinsing of the mouth, particularly if your pet is showing signs of burning or pain in the mouth or throat area. If it has been less than a few hours, and the amount eaten was not overly large, your veterinarian may instruct you on how to properly induce vomiting in your dog, usually using hydrogen peroxide. If hefty quantities of the plant were consumed, or if critical symptoms are starting to develop, a visit to the veterinary clinic may be required for further treatment. Gastric decontamination is often needed to void the various toxins from the patient’s system, after which activated charcoal is utilized to soak up as many of the remaining toxins as possible. 

Treatment after decontamination is generally supportive. IV fluids will be required to fight dehydration as well as to ensure that the proper electrolyte and sugar balances are maintained. Calcium should be avoided as an additive to IV fluids with poisoning caused by leather flower as calcium has a tendency to enhance the effects of the cardiac glycosides. If symptoms expand to include cardiac involvement, then antiarrhythmic drugs such as procainamide, atropine sulfate, or lidocaine may be used in an attempt to regulate the heart rate.

Severe toxicity due to clematis ingestion is rare due to the unpleasant taste and the burning and itching in the mouth, caused by the ranunculin in the plant. Most symptoms from tasting this genus of plants will dissipate within 24 hours. If the quantities ingested or the symptoms necessitate a stay at the veterinary hospital, the recuperating patient should have a quiet, calm setting to return home to in order to speed recovery. This is of particular concern if the heart was affected due to cardiac glycoside involvement as further stress on the heart should be avoided. Anesthesia is often given to facilitate gastric irrigation and may cause short-term difficulties with coordination, and in that case, your dog may be disoriented and  confused when he first returns home.