Be sure to contact a veterinarian as soon as you can, before administering treatment. Hamelia patens: Edible pharmaceutical. Azalea: Symptoms include weakness, upset stomach, drooling, heart failure, depression, possible coma. Get tons of great dog training tutorials, canine gear guides, and the latest doggy discounts. Once your dog returns home, it is important to give him a safe and quiet place to rest for at least a few days. Symptoms include tremors, vomiting, difficulty breathing, and seizures. Similar to many other plants, the alkaloid can cause severe gastrointestinal symptoms and the cardiac glycosides may trigger heart rhythm irregularities.