As a child, I remember my dad trimming the oleander bushes at my grandparent’s house. The sap dripped on to his arms and caused painful rashes. I did not understand how truly poisonous these plants were until years later when I entered veterinary school. We were lucky that none of our pets consumed this pretty but deadly plant.
Oleander contains a cardiac glycoside that is extremely toxic. Just a few leaves will kill a dog. After ingestion, the victim experiences vomiting or it will cause colic in species that do not vomit. It also leads to diarrhea. A short time later, the patient’s heart rate drops and arrhythmias begin. All parts of the plant contain the toxin so extreme care must be taken to insure clippings are not mixed into fodder for ruminants or horses. Since it is toxic to so many species (rabbits, camels, horses, chickens, cattle, llamas, alpacas, dogs, cats, humans), I would assume it is toxic to all creatures until proven otherwise.
If your pet or child is exposed to oleander or any of the other plants that also contain cardiac glycosides (lily-of-the-valley, foxglove, squill and some milkweeds) seek medical attention immediately. Do not wait until clinical signs develop. With proper care, most patients will make a complete recovery without any long term affects to their hearts or gastrointestinal systems.
Oleander comes in a variety of colors including red, pink and white. Please use caution when working around these deadly beauties.