Yes, Wahoo is toxic to dogs!
Dogs accidentally consuming the Wahoo 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).
Wahoo consumption is also toxic to Cats and Horses.
Toxic Principles Of Wahoo: Alkaloids, Cardenolides.
More Info About The Wahoo Plant
Scientific Name: Euonymus occidentalis
Family: Celastraceae.
Also known as: Burning Bush, Spindle Tree.
The answer is based on information found on The American Society for the Prevention of Cruelty to Animals (ASPCA) website.