Spindle Tree Poisoning in Cats

Spindle Tree belongs to the Celastraceae family, with the scientific name, Euonymus atropurpurea. Every part of this shrub is considered to be highly poisonous, having strong laxative and emetic effects. While it has been used in folk medicine, this plant should not be used for treating cats or dogs.

The spindle tree (also called burning bush, wahoo, summer cypress and strawberry bush) is highly toxic to cats. This bush contains both alkaloids and cardenolides, which can lead to some dangerous heart issues for your pet, especially if he ate a large amount of this plant material.

Your cat won’t show symptoms of poisoning or illness until the toxins in the spindle tree have been absorbed throughout his system. Symptoms include:

• Abdominal pain
• Excessive drooling
• Coughing
• Vomiting
• Diarrhea
• Constipation (may follow diarrhea)
• Physical weakness
• Increased body temperature (hyperthermia)
• Shock
• Dilated pupils
• Headache
• Dizziness
• Tremors
• Exhaustion
• Kidney and liver involvement (develops within 8 hours)
• Breathing difficulties
• Bradycardia (slowed heart rate)
• Tachycardia (elevated heart rate)
• Arrhythmia (irregular heart rate)
• Cardiac arrest (in large doses)
• Blindness
• Unconsciousness
• Coma (develops within 12 hours)
• Death (with large doses)

The dangerous toxins within the spindle tree include:

• Evomonoside (which converts to digitoxigenin, a heart toxin)
• Evonoside (a heart toxin)
• Glycoside, evobioside (heart toxin)

Ingesting part of the spindle tree can cause poisoning in cats. The availability of this plant, combined with boredom and a lack of access to cat-friendly plants, can lead cats to experiment with eating the plant material.

Once you know your cat is sick and you believe he may have eaten from your spindle tree, cut a sample of the shrub for your vet to examine. If you are able to collect them, bring samples of your cat’s vomit and stool with you as well. Because the toxins in spindle tree have such strong emetic and laxative effects, you’ll be able to find what you need to take with you. 

Your vet will give your cat a full physical, run blood tests to verify his magnesium and potassium levels, and get an electrocardiogram, which allows her to monitor your cat’s cardiac functions. Your cat will have his blood pressure and oxygen saturation rate taken.

The blood work includes a CBC and BUN (blood urea nitrogen) and electrolyte panel. The vet may also take a urine sample and study your cat’s fecal sample and vomit to confirm that he was poisoned by spindle tree. His blood glucose level will also be tested because the cardiac toxins can alter your cat’s blood sugar, making it fall to a life-threatening level. The vet may also take X-rays of your cat’s abdomen and chest, which allows her to verify his lung function.

Your vet has to know how much of the plant your cat ate so she can order the most appropriate treatment. If your cat only ate a little bit, he may only need to have lost fluids and electrolytes replaced and have even more vomiting induced, using a hydrogen peroxide solution, which helps him get rid of the rest of the plant remaining in his stomach. He may also have activated charcoal introduced into his digestive system. This helps bind the remaining toxins, which will then exit his body via defecation.

Treatments for spindle tree poisoning also rely on your cat’s individual symptoms. If he ate a large amount of the shrub, his potassium level may be dangerously high. In this case, he will be given Fab fragments, which is a digoxin antibody derived from sheep. If he has developed convulsions, the vet may prescribe medication given through his IV. Depending on the severity of his symptoms, your cat may stay in the vet’s clinic overnight until he has stabilized and begun recovering.

If you get your cat to veterinary treatment as soon as you realize he’s been poisoned, he stands a better chance of making a full recovery. Because liver damage can develop inside of 8 hours, with your cat becoming comatose within 12 hours, it’s vital to get immediate treatment.

In order to prevent future cases of poisoning, remove spindle trees from your cat’s environment or limit his outdoor access to prevent contact with the plant in neighboring yards.