Yes, Perennial Pea is toxic to dogs!
Dogs accidentally consuming the Perennial Pea plants can show the following clinical symptoms: Vomiting, Prolonged Depression, Incoordination, Hypersalivaton, Sleepiness Or Excitation, Dilated Pupils, Low Body Temperature, Low Blood Pressure, Coma, Seizure And Death (In Rare Cases).
Perennial Pea consumption is also toxic to Cats and Horses.
Toxic Principles Of Perennial Pea: Aminoproprionitrite.
More Info About The Perennial Pea Plant
Scientific Name: Lathyrus latifolius
Family: Fabaceae.
Also known as: Sweet Pea, Everlasting Pea.
The answer is based on information found on The American Society for the Prevention of Cruelty to Animals (ASPCA) website.