Yes, Arrow-Head Vine is toxic to dogs!
Dogs accidentally consuming the Arrow-Head Vine 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).
Arrow-Head Vine consumption is also toxic to Cats and Horses.
Toxic Principles Of Arrow-Head Vine: Insoluble calcium oxalates.
More Info About The Arrow-Head Vine Plant
Scientific Name: Syngonium podophyllum
Family: Araceae.
Also known as: Nephthytis, Green Gold Naphthysis, African Evergreen, Trileaf Wonder.
The answer is based on information found on The American Society for the Prevention of Cruelty to Animals (ASPCA) website.