Boxwood Tree Poisoning in Dogs

A boxwood is a flowering evergreen tree and is most often used in gardens or yards as shrubs or dividers. The entire tree is poisonous, both orally and topically, so it is best not to have them anywhere your dog will be. It does not take much to cause enough toxicity to be fatal without treatment if your dog is small (Toy Poodle, Shih Tzu) or not in good health. The alkaloid in the plant prompts congestion of the heart, lungs, liver, kidneys, and spleen which will eventually cause organ shutdown and death.

The Boxwood Tree is from the Buxaceae plant family, and contains alkaloids, which are toxic to dogs. While the entire plant is toxic, the leaves are especially poisonous to dogs and other small animals. These plants, commonly used as hedges, contain steroid alkaloids. The solanum-type steroid alkaloid in the boxwood are ethers that cause skin irritation with contact as well as many other symptoms, some serious, if eaten. For example, if your dog eats a significant amount (more than a few leaves), this will likely cause vomiting and diarrhea, which can lead to dehydration. In addition, if your dog is older than 10, or has any underlying health problems, just eating one leaf can cause significant stomach irritation, respiratory, and heart failure. This will lead to death if not treated right away, so be sure to take your dog to the veterinarian or animal hospital if your dog eats any part of a boxwood tree.

Symptoms differ depending on the method of exposure, oral or topical. For oral poisoning, the amount eaten can cause symptoms to differ as well.

Oral Poisoning

• Colic
• Coma
• Confusion
• Convulsions
• Death
• Diarrhea
• Dizziness
• Drooling
• Extreme thirst
• Heart failure
• Inability to walk straight
• Increased heart rate and breathing
• Irritation or excitability
• Lethargy
• Nausea
• Paralysis
• Respiratory failure
• Seizures
• Vomiting

Topical Poisoning

• Dermatitis
• Excessive itching
• Skin irritation
• Skin redness

 Types

• Oral boxwood tree poisoning is caused by the ingestion of any part of the boxwood tree.
• Topical boxwood tree poisoning is caused by exposure of the skin to any part of the boxwood tree or anything containing parts of the boxwood tree.

The cause of boxwood tree poisoning in dogs is exposure to the plant either directly or indirectly. On the skin, the liquid from the tree can cause irritation, redness, and itching. If eaten, boxwood tree toxin may produce vomiting, diarrhea, dizziness, and if not treated right away, possible respiratory failure and death.

If you saw your dog eat any part of a boxwood tree, go to the veterinarian or animal hospital immediately and try to bring a piece of the tree with you to show the veterinarian. This will help speed up the diagnosis so your veterinarian can start a treatment plan faster. A complete physical examination will be done, which includes body temperature, weight, heart rate, blood pressure, respiration rate, breath sounds, and reflexes. The veterinarian will also take a look down your dog’s throat to see if there are any parts of the plant still in the airway. This procedure is usually done with an endoscope, which is a long, thin tube with a light and camera on the end. The veterinarian is also able to remove pieces of the plant with a clamp on the end of the endoscope.

Blood and urine tests will be done, including a complete blood count (CBC), blood gas, biochemistry profile, and liver enzyme count. If your dog has been vomiting, the veterinarian will want to do a radiograph of the abdomen to see if there are any residual parts of the plant still intact. An MRI, CT scan, and ultrasound may also be done to give the veterinarian a more detailed look at what is going on. An electrocardiogram (ECG) is sometimes necessary to measure the electrical and muscular performance of the heart.

Your dog will be given fluids through an IV and oxygen if needed when the veterinarian finishes the physical examination. Fluids help keep your dog hydrated and flush the system as well. If it has not been longer than two hours since your dog ate the boxwood, the veterinarian will use a medication to induce vomiting. She will also give your dog activated charcoal, which absorbs the toxins in your dog’s system so they do not do more harm while leaving the body. Stool softener and laxatives may also be given to get some of the toxins out that way. The veterinarian will probably administer atropine and continue to monitor your dog’s vital signs overnight.

The prognosis for your dog is excellent if you were able to get to the veterinarian for treatment right away. Recovery is not a long process, but your veterinarian may suggest cage rest for a few days. Call your veterinarian if you have any concerns or questions. Make sure you get rid of your boxwood trees or block access to them so your dog does not get sick again.