Hydrangea Poisoning in Cats
Hydrangea Poisoning in Cats - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost
What is Hydrangea Poisoning?
The reason that hydrangea present a potential threat to cats is because the buds and leaves of the plant contain cyanogenic glycosides called “amygdalins”. When these glycosides are digested, they mix with water and release hydrocyanic acid inside the body. This deprives the cells of oxygen and produces a negative response in the body. The plant material can also cause skin irritation upon contact. This is especially the case in cats who have sensitive skin or skin disease.
Hydrangea, or hills of snow as it is often called, is a common garden shrub used in landscaping all over the United States. It is scientifically known as Hydrangea macrophylla of the Saxifragaceae family of plants, although it can also be called Hortensia or seven bark. Hydrangea are popular because of their large clusters of small white flowers, which can resemble balls of snow. The flowers can come in pinks, whites or blues depending on the type of plant and the pH of the soil. The plant is hardy and the flowers bloom all summer and well into the fall. 
Hydrangea Poisoning Average Cost
From 400 quotes ranging from $200 - $600
Average Cost
$400
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Symptoms of Hydrangea Poisoning in Cats
Usually, only a mild digestive disturbance will follow the consumption of hydrangea. Severe reactions are rare but can occur. All signs to watch for are listed as follows:
  • Nausea
  • Vomiting
  • Diarrhea (may contain blood)
  • Abdominal pain 
  • Depression 
  • Dermatitis (in hypersensitive cats)
  • Dyspnea (difficulty breathing)
  • Limb stiffness
  • Seizures
  • Coma
Causes of Hydrangea Poisoning in Cats
Hydrangeas are very common plants found in many gardens across the country. Clippings of the showy flower clusters are often kept inside the home and used in floral decorations or bouquets. The flowers can also be dried and used as permanent decor. Both dried and fresh flowers and leaves contain the toxins that can make your cat ill. Hydrangea poisonings are rare, as a very large amount of plant material must be ingested before the body becomes overwhelmed.
Diagnosis of Hydrangea Poisoning in Cats
If you saw your cat eating a hydrangea plant, diagnosis should be straightforward. If you are unsure if the plant was indeed a hydrangea, bring in a small clipping for the veterinarian to identify the plant. If you did not witness the cat eating any plant material, a more thorough assessment may be needed to discover what has caused the gastrointestinal distress. You may be asked to provide your cat's full medical history so that other health issues can be ruled out. You may also be asked if you allow your cat outdoors, or if you have any plants or bouquets in your home. 
The veterinarian will then perform a complete physical examination of the cat to note all symptoms that the cat is exhibiting. The vet may use a stethoscope to listen to the cat's heartbeat and breathing. In cats who are experiencing severe reactions, labored breathing may be noted. Blood samples will be taken from the cat for tests to be run. These tests generally include a complete blood count and a biochemical profile to measure the contents of the bloodstream. Urinalysis should also be used to assess how the kidneys and liver are functioning.
Treatment of Hydrangea Poisoning in Cats
Treatment for cats who have ingested hydrangea is mainly symptomatic. Cases may range greatly in severity, with most being relatively mild. Serious instances may require hospitalization.
Remove Stomach Contents 
This may be done either by inducing the cat to vomit with hydrogen peroxide or by performing a gastric lavage (stomach pumping). Removing all remaining plant material from inside of the cat will prevent the body from absorbing any more toxins.
Supportive Care 
If your cat has been expelling waste for a long period of time, it may become dehydrated. Administering fluids intravenously can help bring volumes back up and stabilize body functions. The cat should be kept as comfortable as possible throughout this process.
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Recovery of Hydrangea Poisoning in Cats
Consuming hydrangea is generally not a life-threatening situation, although it should be taken seriously to ensure the best outcome for the cat. If the cat recovers from the illness, no lasting health effects should be seen. Keep any floral arrangements out of your cat's reach or even out of the home if they contain hydrangea. The only way to limit your cat's exposure to the common shrub is to keep it indoors where you can monitor which plants it interacts with.
Hydrangea Poisoning Average Cost
From 400 quotes ranging from $200 - $600
Average Cost
$400
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Hydrangea Poisoning Questions and Advice from Veterinary Professionals
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Abyssinian
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Franny
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13 Years
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6 found this helpful

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My pet has the following symptoms:
Vomiting, Diarrhea, No Appetite
My cat ate some hydrangeas and went through several days of diarrhea, for which her vet gave her fluids, Metronidazole and Cerenia. She was back to normal for almost 5 days and then went through the same cycle of throwing up, diarrhea, and lack of appetite. I gave her one Metronidazole and 1/2 Cerenia tab when I noticed the symptoms returning, and she was back to normal again by the next day. Is it possible for her to have remnants still in her system? Should I be concerned she will relapse again, in other words?
Aug. 9, 2018
6 Recommendations
Thankfully hydrangea poisoning in cats is self limiting although some supportive and symptomatic care may be required; after five days I would imagine that she should be almost normal again but if there is a relapse of symptoms and no real improvement you should return to your Veterinarian to be on the safe side. Regards Dr Callum Turner DVM
Aug. 10, 2018
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Unknown/Domestic Shorthair
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Mimi
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9 Years
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5 found this helpful

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5 found this helpful

My pet has the following symptoms:
Vomiting
My cat ate some hydrangea petals around 10pm last night (we had a dinner party and they were a gift brought in a vase). She showed no noticeable symptoms of irritation until now (4am), when she vomited chunks of food, along with some hydrangea petals. It was a very hot day, so she drank a bunch of water prior to nibbling on the petals. I think she vomited all of them, but I can’t be sure. Is there anything else I should watch for, or should I take her into the vet today?
June 25, 2018
5 Recommendations
Typically hydrangea poisoning results in self limiting gastrointestinal symptoms including vomiting and diarrhoea; keep an eye on her and ensure that she is drinking and starting to eat. If there is no improvement, other symptoms present or she gets worse visit your Veterinarian for an examination to be on the safe side. Regards Dr Callum Turner DVM
June 26, 2018
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Unknown/Bengal
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Watson
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6 Years
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My pet has the following symptoms:
Vomiting
My cat ate part of a hydrangea leaf and vomited about 5 minutes later, expelling the leaf. He appears fine now but should I be worried that there could be more in his stomach?
May 14, 2018
Answered by Dr. Michele K. DVM
6 Recommendations
If Watson vomited the part of the leaf that he ate, you should be fine to monitor him for any further signs. Things to watch for would be further vomiting, diarrhea, loss of appetite, lethargy, or itchy or irritated skin. If any of those things happen, he should be seen by a veterinarian to have treatment.
May 14, 2018
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European Shorthair
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sOPHIA
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2 Years
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2 found this helpful

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My pet has the following symptoms:
None Yet
Hello, A few hours ago my cat chew on the leaves of a hydrangea, but she only ate like the tip of one leaf. She didn't show any symptoms. Now she just ate half a leaf while i was out of the room for a few minutes. Read online that it was harmful so i panicked. I put the flower even higher on the furniture and now i'm scared that she may get sick. It got a little better after i read the info on this site which is much more complete than anything i found online about the subject. Should i just observe her and rush her to the vet if she vomits or anything? I'm thinking she may vomit because of fur balls (as that's why she ate the leaf) and i worry that i wouldn't be able to tell if the vomits because of fur or poisoning. Is that half of a leaf a semnificant quantity for her? She's a small cat, about 2 - 2.5kilos. Thanks
Feb. 27, 2018

2 Recommendations
Most likely there will be some gastrointestinal upset from the ingestion of the Hydrangea leaf, more serious symptoms are usually due to consumption of larger quantities; it is difficult to determine how much would be toxic as levels vary between plants and even leaves on the same plant. Moving the Hydrangea to a different area or from the house altogether would be best long term, monitor her for respiratory difficulty or any other concerning symptoms; if you are concerned don’t hesitate to visit your Veterinarian or an Emergency Veterinarian to be on the safe side. Regards Dr Callum Turner DVM
Feb. 27, 2018
Thank you for you answer, I'm so relieved. For now she didn't give any signs that should concern me, she slept and played. The hydrangea is in a room where she only stays when i'm present, and as soon as it gets warmer it will go in the balcony. I got really worried as i saw it listed in an article 3rd place poison wise, after the lilium and poisentia and i know that the lily is pretty dangerous to cats even in small quantities.
Feb. 27, 2018
sOPHIA's Owner
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American shorthair tabby
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Gussy
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5 Years
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0 found this helpful

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My pet has the following symptoms:
No Symptoms
about an hour ago my cat snuck into the room where I keep the plants while I was watering the plants. The door is always closed as Gussy has a tendency to eat crazy things (As a kitten he climbed into a pot of Vegetarian chili with onion and garlic, eggplant, my clothes). He ate a dried up Hydranga leaf. I have been monitering him and he ate breakfast and has been running around playing. He a small 5 year old cat, always indoors. I found him and his two brothers under a car in Venice Beach CA, so he is pretty used to injesting things he shouldn't. Should I continue monitering? induce vomiting? or rush him to the vet?
Hydrangea Poisoning Average Cost
From 400 quotes ranging from $200 - $600
Average Cost
$400
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