Dog Hobble Poisoning in Cats

Dog hobble contains a type of grayanotoxin called “tetracyclic polyol andromedotoxin” in its foliage, blossoms, nectar, and stems. This toxin is poisonous to most mammals, including cats. These toxins bind to the sodium channels within the body's cells, stopping the cells from deactivating and keeping them in a positively charged state. This causes a very dangerous response in the body, with cardiac arrest and respiratory failure often following. While poisoning by dog hobble is relatively rare in cats, it has the potential to be fatal and should be treated as a medical emergency.

The dog hobble plant, also called “fetterbush”, “dog laurel” or “black laurel”, is a common shrub that comes in various forms and can be found throughout the United States. It is found most often in the southeastern states, as it cannot winter outside in very cold climates. The scientific name of dog hobble is Leucothoe sp. and it is a part of the Ericaceae family.  Dog hobble has leathery green leaves and it produces tendrils of delicate, white, bell flowers. The plant often blooms around mid-spring. It has red stems which grow dense and low to the ground, making it very hard to walk through, hence its name. 

Ingestion of any part of the dog hobble plant can produce a life-threatening cardiac response and is a medical emergency. Do not wait for multiple symptoms to develop. Signs to watch for are listed as follows:

• Nausea
• Vomiting
• Diarrhea 
• Excessive drooling 
• Nasal discharge 
• Weakness 
• Ataxia (unstable gait)
• Depression 
• Behavioral changes 
• Abdominal pain 
• Low blood pressure 
• Bradycardia (slowed heartbeat)
• Blindness
• Numbness
• Seizures
• Paralysis 
• Cardiovascular collapse 
• Coma

Dog hobble is often used in gardens for its ornamental flowers and lush leaves, however it also grows in forests and woodlands as it is a native plant. This means that if your cat has access to the outdoors, it has a heightened risk of coming into contact with this toxic plant. Because the grayanotoxins in the dog hobble are so strong, even consumption of a very small amount can be fatal, especially to a cat due to their small body size. The leaves cause the mouth to burn upon chewing, stopping most cats from taking a second bite.

If you witnessed your cat eating a dog hobble or if it has begun to exhibit symptoms of poisoning, rush it to the nearest veterinary clinic or animal hospital. If you saw your cat eating plant material, but are unsure of what it was, bring a small clipping of the plant along with you so that the veterinarian can identify it. A diagnosis will often be made after treatment has been started to stabilize the cat. In some cases, a diagnosis will only be made in an autopsy post mortem.

The veterinarian will perform a complete physical examination of the cat, noting all symptoms that have manifested. While listening to the cat's heart with a stethoscope, the vet may find that the heartbeat is very slow and that the pulse is weak. This is a signal that the heart is beginning to fail. Full blood work should be run to determine the cat's overall health. This will generally include a complete blood count and a biochemical profile to measure all mineral and cell levels in the blood stream. Dog hobble poisoning will have to be differentiated from other health problems that cause gastrointestinal and cardiac distress. 

There is no known antidote for Dog Hobble poisoning. The best way to help a cat survive the episode is to provide supportive care and treat symptoms as they arise.

Supportive Care 

Antiemetics may be given to help the cat stop vomiting. Intravenous fluids may be administered to help increase fluid volumes in the body. A medication such as atropine may be given via IV to help regulate the heart rate. The cat's heartbeat should be monitored throughout treatment. Vasopressors can be given to constrict blood vessels, therefore increasing blood pressure.

Activated Charcoal

If a very short amount of time has passed since the plant was ingested, administering activated charcoal can help bind the toxins in the stomach, preventing digestion. The cat must still be conscious for this treatment to be effective.

If only a minuscule amount of plant material was consumed, creating a mild reaction in the cat, it may be sent home to recover under close watch. Most cases are severe and require immediate hospitalization. The ingestion of grayanotoxins, such as the ones contained in the dog hobble plant, can often be fatal to cats due to how fast they shut down the body. Symptoms generally last from 24 hours to several days. If the cat does survive the incident, no lasting effects should be caused by the poisoning. 

Keeping your cat indoors may be the only way to limit exposure to the dog hobble plant, especially if you live in an area where it grows wild. While removing the shrub from your own garden can decrease the chance that your cat will come into contact with it, the risk of it growing in surrounding gardens will remain. It may be a good idea to research the plant so that you can easily identify it in the case of an emergency.