Arbutin, Grayanotoxin (aka. Andromedotoxin, Rhodotoxin, and Acetylandromedol), Arbutin glucoside
excessive drooling, weakness, vomiting, diarrhea, depression of the central nervous system, abnormally low blood pressure, cardiovascular collapse, coma and death.
All parts of the plant are poisonous especially the foliage, contain some glycosides, to include Andromedotoxin which is chemically similar to turpentine. Andromedotoxin like turpentine will burn the mouth, which tends to discourage potential victims from consuming dangerous quantities. In order for the development of toxic signs, an animal will need to ingest 0.2% by weight of green leaves. To put it another way, a 60lb dog would need to eat a little less than 2 ounces for toxic signs to develop.
Prevent any further ingestion of the plant and provide supportive care. Seek Veterinary Attention.
Toxic to Dogs, Toxic to Cats