Everlasting Pea Poisoning in Dogs

The everlasting pea plant is one of the several flowers in the Lathyrus family of plants that can cause a serious and irreversible disorder known as lathyrism that can cause severe pain and paralysis to those individuals who consume large amounts of these plants over time. Lathyrism is one of the oldest recorded neurotoxic diseases, frequently striking humans when plants in this family were used as a staple during times of famine. This disorder is more common in grazing animals like horses and sheep than in predators like canines and felines.

The everlasting pea plant (Lathyrus latifolius) is a perennial flower in the Lathyrus genus that can be found both in ornamental gardens and growing wild along roadsides throughout the world.

If your pet overeats from the everlasting pea plant in one setting, the symptoms are going to be the typical signs you would see when your pet eats something that doesn’t agree with them. This can include vomiting, diarrhea, abdominal pain, and even lethargy. The symptoms of lathyrism occur after chronic exposure to uncooked or undercooked plants in the Lathyrus family and can include: 

• Aortic rupture
• Death
• Head pressing
• Hind leg paralysis
• Lethargy
• Pacing
• Seizures
• Skeletal deformity
• Tremors
• Urinary incontinence
• Weakness

Types

Lathyrism, the disorder caused by a toxin that is present in all members of the Lathyrus genus, can affect different people and animals in different ways, depending on which system in the body it affects. The types of lathyrism are:

Osteolathyrism - Osteolathyrism is a form of lathyrism that weakens the connective tissue between the muscles and the bones.

Neurolathyrism - Neurolathyrism is the most common form of lathyrism and is characterized by weakness progressing to paralysis in the hind legs. 

Angiolathyrism - In this type of lathyrism, the toxin attacks the structure of the blood vessels themselves, leaving the patient more susceptible to tears in the vessels and aneurysms.

Plants in the Lathyrus genus, such as the everlasting pea plant, contain several compounds that can affect the connective cells in the body. The compounds most responsible for the degradation of the connective tissue are beta-aminopropionitrile (BAPN), and oxalyldiaminopropionic acid (ODAP). BAPN is also used in veterinary medicine to treat severe cases of rheumatoid arthritis.

Lathyrism is uncommon in dogs as they don’t tend to graze on plants on an ongoing basis, and this disorder takes time to build up. There are several disorders that can cause the characteristic paralysis in the hindquarters including degenerative myelopathy, tumors on the spinal cord, and wobbler syndrome. Some of the other symptoms, such as head pressing and seizures, can be indicative of other life-threatening conditions as well. 

If your canine companion is showing signs of lathyrism, it is important to get your animal into the veterinary clinic to rule out disorders like brain tumors, infections of the nervous system, and sodium imbalances. An MRI and X-ray imaging may be requested to this end, as well as the more conventional blood chemistry testing. The animal’s diet will be thoroughly scrutinized if the source of the lathyrism is unknown,  however, the final diagnosis is often based on symptomatology and history.

Although lathyrism is one of the oldest recorded neurotoxic diseases, the mechanism by which it causes the damage to the tissues is still poorly understood. Although the removal of the toxin from the dog’s diet in the early stages of the disorder sometimes results in the spontaneous reversal of the condition, it is more common for the spastic paraparesis to remain indefinitely. The condition is accompanied by extreme stiffness and pain, so pain mitigation medications are often prescribed as well. 

If excessive volumes of plant material have been consumed by your pet or if your dog is particularly sensitive to the compounds found in the plant, considerable nausea and vomiting may develop. Dehydration is one of the biggest dangers that comes with extensive vomiting and diarrhea, and your companion should be monitored carefully for signs of dehydration such as sunken eyes, exhaustion, excessive panting, loss of elasticity in the skin, and unsteadiness when standing. These symptoms may signal that the dog is in acute distress, and your veterinarian should be contacted immediately for further instructions.

It is best to avoid exposing your pet to everlasting pea plants, especially on a regular basis. Even in situations where the exposure to the plant was brief rather than chronic, eating too much vegetation can cause acute gastrointestinal distress or blockages in canines. A pet who suddenly develops the urge to eat large amounts of vegetation or other inappropriate items may be responding to brain lesions, vitamin deficiencies, or circulatory abnormalities and should be checked by a veterinarian. The best way to keep your pet safe from toxins of any sort is by careful observation of their behavior and environment.