Yes, Lemon Verbena is toxic to dogs!
Dogs accidentally consuming the Lemon Verbena 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).
Lemon Verbena consumption is also toxic to Cats and Horses.
Toxic Principles Of Lemon Verbena: Essential oils.
More Info About The Lemon Verbena Plant
Scientific Name: Aloysia triphylla
Family: Verbenaceae.
Also known as: Lemon Beebrush.
The answer is based on information found on The American Society for the Prevention of Cruelty to Animals (ASPCA) website.