Lily of the valley, or convallaria, is not a true lily like the Easter or Asiatic lily, but is still toxic to dogs, humans and other animals. If your dog chews on the plant or eats pieces of it, he can become seriously ill and should receive immediate veterinary treatment.
Lily of the Valley
While true lilies can cause kidney failure, the toxic components of lily of the valley affect your dog's heart. These components are called cardiac glycosides, and the symptoms they cause include irregular heartbeats, a slowed heart rate and seizures. Vomiting and diarrhea are the other symptoms of lily of the valley poisoning. The severity of the symptoms depends on many factors, including your dog's size and how much of the plant he ingested. Severe cases can result in death, however, so it's vital to contact your veterinarian immediately if you suspect your dog has chewed on or swallowed lily of the valley.