Azaleas (Photo credit: cbellh47)
All parts of Nerium oleander are considered to be toxic, as they contain cardiac glycosides that have the potential to cause serious effects—including gastrointestinal tract irritation, abnormal heart function, hypothermia and even death.
The poisonous principle in Ricinus communis is ricin, a highly toxic protein that can produce severe abdominal pain, drooling, vomiting, diarrhea, excessive thirst, weakness and loss of appetite. Severe cases of poisoning can result in dehydration, muscle twitching, tremors, seizures, coma and death.
Cylamen species contain cyclamine, but the highest concentration of this toxic component is typically located in the root portion of the plant. If consumed, Cylamen can produce significant gastrointestinal irritation, including intense vomiting. Fatalities have also been reported in some cases.
This plant contains components that can produce gastrointestinal irritation, as well as those that are toxic to the heart, and can seriously affect cardiac rhythm and rate.
Taxus spp. contains a toxic component known as taxine, which causes central nervous system effects such as trembling, incoordination, and difficulty breathing. It can also cause significant gastrointestinal irritation and cardiac failure, which can result in death.
Common garden plants popular around Easter, Amaryllis species contain toxins that can cause vomiting, depression, diarrhea, abdominal pain, hypersalivation, anorexia and tremors.
Ingestion of Colchicum autumnale by pets can result in oral irritation, bloody vomiting, diarrhea, shock, multi-organ damage and bone marrow suppression.