Are Hydrangeas Poisonous To Dogs

Dogs or cats that consume enough hydrangea leaves, flowers and/or buds can suffer from vomiting and diarrhea. In severe cases, hydrangea poisoning can cause lethargy, depression and confusion.

Why Are Hydrangeas Poisonous To Dogs?

All parts of hydrangeas (buds, flowers, leaves, stems) are poisonous to dogs, making no part of this plant safe to chew on. But what exactly is it about these stunning shrubs that makes them toxic to our canine companions?

“They [hydrangeas] contain cyanogenic glycosides similar to that found in apple seeds, peach, apricot, plum, and cherry pits,” says Renee Schmid, DVM, DABVT, DABT, and Senior Veterinarian Toxicologist at the Pet Poison Helpline.

Although it may be tempting to remove all hydrangeas and anything that resembles them ASAP, there is some good news that might ease your worries and make you reconsider.

“Even though hydrangeas contain cyanogenic glycosides that are toxic to animals, the amount of hydrangea plant material a dog would need to ingest for cyanide poisoning is very large, so poisoning rarely occurs,” Schmid says.

Want to keep your hydrangeas or begin to grow them in your garden? Try placing them in the front yard away from your pets or using a gate to fence them off from your furry friend.

Signs of Hydrangeas Poisoning in Dogs

With plants continuously ranking on the ASPCAs top 10 pet toxins list, its important to know what signs of poisoning to look for if your dog has gotten into hydrangeas.

When it comes to hydrangea poisoning, Schmid says the most typical symptoms are those related to gastrointestinal (GI) irritation.

“Vomiting, lethargy, and diarrhea are most common to see,” she says. “If true cyanide poisoning were to occur, signs include: hypotension, brick-red gum coloring, heart rhythm abnormalities, almond-flavored breath, hyperventilation, difficulty breathing, low oxygen levels, cyanosis, ataxia, and tremors/seizures.”

Causes of Hydrangea Poisoning in Dogs

The toxin the hydrangea contains is known as cyanogenic glycosides. Plants in this family have contained cyanogenic glycosides for hundreds of years and are believed to act as a natural defense mechanism of the plant. It is believed to help the plant ward off bacteria, viruses, and fungi, as well as deter insects and herbivores.


How poisonous is hydrangea?

Toxicity to pets

This common garden shrub has a beautiful, colorful flower (e.g., pink, blue, white, depending on the soil of the pH). This shrub contains cyanogenic glycosides, with higher concentrations found in the leaves and flowers. When ingested by pets, it can cause vomiting, diarrhea and lethargy.