# Is Hortensia Toxic to Cats? Hydrangea Poisoning Facts Is hortensia toxic to cats? Yes. Hortensia is another name for hydrangea, and the plant is listed as toxic to cats, dogs, and horses [1][2]. The good news is that serious cyanide poisoning from a small nibble is rare, and most cases amount to stomach upset [1][2]. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - Hortensia and hydrangea are the same plant, and every part (leaves, flowers, stems, buds) is considered toxic to cats [1][2]. - The toxic principle is a cyanogenic glycoside, a compound that can release cyanide when the plant tissue is chewed or damaged [1][2]. - The most common signs are vomiting, diarrhea, and depression, and true cyanide intoxication is rare [1][2]. - A single small bite often causes mild stomach upset, while a large amount of plant material is a bigger concern and needs a call to your veterinarian or a poison control line. - Do not make your cat vomit unless a veterinarian tells you to. ## Is Hortensia Toxic to Cats? Yes, and It Is the Same Plant as Hydrangea Hortensia is simply another common name for hydrangea [1][2]. The ASPCA lists additional common names as Hydrangea, Hills of Snow, and Seven Bark, with the scientific name Hydrangea arborescens in the family Hydrangeaceae [1][2]. So if you have read that hydrangeas are poisonous to cats, the same warning applies to a plant labeled hortensia. The ASPCA classifies hortensia as toxic to cats, dogs, and horses [1]. That classification is based on the plant's toxic principle, a cyanogenic glycoside, and the clinical signs reported after ingestion [1][2]. ### Which Parts of the Plant Are Toxic? All parts of the plant should be treated as potentially toxic, including the leaves, stems, flowers, and buds. The cyanogenic glycoside is distributed through the plant tissue, and the amount present can vary with the plant, the season, and the part eaten. Because that variability is not well established in veterinary research for every hydrangea variety, the safest approach is to assume any part your cat chews is a possible exposure. ### Are Cut Flowers, Dried Flowers, and Bouquets a Risk? Yes. A hydrangea bouquet on a table, a dried arrangement on a shelf, or a single bloom knocked to the floor is still hydrangea. Cats often bat at flowers and then groom their paws, so they can swallow plant material without you seeing a full bite. Vases are a double risk because the water can hold plant compounds and bacteria. If your cat has access to cut hortensia, treat it as an exposure and remove the plant from reach. ### Is Hydrangea Cyanide Poisoning in Cats Common? Real cyanide intoxication is rare [1][2]. The ASPCA notes that cyanide intoxication is rare and that ingestion usually produces more of a gastrointestinal disturbance [1][2]. That matches the broader pattern seen in small animal plant poisonings, where most exposures cause mild to moderate clinical signs [3]. Hydrangea macrophylla appears among the plants responsible for pet intoxications in one European survey of plant poisonings in domestic animals [3]. ## The Toxic Principle: Cyanogenic Glycosides and What They Do Cyanogenic glycosides are plant compounds that can release hydrogen cyanide when the plant cells are broken down by chewing, crushing, or digestion. In theory, cyanide blocks the body's ability to use oxygen in cells, which is why large exposures are treated seriously. In practice, the amount released from a casual bite of an ornamental hydrangea is usually small, and the cat's main problem is stomach irritation instead of full cyanide poisoning [1][2]. This is why the reported signs in cats are mostly digestive and behavioral: vomiting, depression, and diarrhea [1][2]. If a cat eats a large quantity of plant material, more cyanide could be released, and that is when a veterinarian may want to see the cat quickly instead of wait at home. ## Hortensia Poisoning Symptoms in Cats The classic signs listed for hortensia and hydrangea are vomiting, depression, and diarrhea [1][2]. Depression in this context means the cat seems dull, quiet, or less responsive than usual, not clinical depression. ### Common Signs to Watch For - Vomiting, sometimes repeated - Diarrhea - Drooling or lip smacking - Reduced appetite - Acting quiet, tired, or withdrawn - Pawing at the mouth or showing mouth discomfort ### Signs That Suggest a More Serious Exposure - Weakness, wobbling, or collapse - Fast breathing, open-mouth breathing, or labored breathing - Bright red or abnormally colored gums - Tremors, twitching, or seizures - Vomiting that will not stop - Any sign that appears suddenly and worsens over minutes ### Timeline: When Do Signs Show Up? Signs usually appear within a few hours of ingestion, and many cats show stomach upset first. The exact timing depends on how much was eaten, whether the cat had food in the stomach, and how much plant material was chewed. If your cat ate hortensia and is still completely normal several hours later, that is reassuring but not a guarantee. Keep watching for the rest of the day, and call your veterinarian if anything changes. ## Cat Ate Hydrangea Leaves: What to Do Right Now Stay calm and gather information. Note how much plant material is missing, which part of the plant was chewed, and when it happened. Take a photo of the plant and the chewed area if you can. Then call for advice. Call one of these: - Your own veterinarian or the nearest emergency veterinary clinic - ASPCA Animal Poison Control Center at (888) 426-4435 - Pet Poison Helpline at (855) 764-7661 Poison control lines may charge a consultation fee, and they can advise your veterinarian directly. Have your cat's weight, age, and any health conditions ready. ### Do Not Induce Vomiting Unless Told To Do not make your cat vomit on your own. Do not give hydrogen peroxide, salt water, milk, oil, or home remedies. Inducing vomiting can cause harm, especially if the cat is already weak, breathing hard, or showing neurologic signs. A veterinarian will decide whether decontamination is safe and appropriate for your cat. ### What to Bring to the Vet Bring the plant or a clear photo, the estimated amount eaten, the time of ingestion, and a list of your cat's medications and health problems. If your cat vomited, a photo of the vomit can help your veterinarian judge how much plant material came up. ## How Veterinarians Treat Hortensia Poisoning in Cats Treatment depends on the signs and the amount eaten. For a mild exposure with one episode of vomiting, your veterinarian may recommend monitoring at home with clear instructions on what to watch for. For heavier ingestion or worsening signs, expect a clinic visit. ### Decontamination and Supportive Care If the exposure was recent and your cat is stable, a veterinarian may discuss decontamination options, which can include inducing vomiting in a controlled setting or giving activated charcoal. These steps are not right for every cat, and the decision is made case by case. Supportive care often includes intravenous fluids, anti-nausea medication, stomach protectors, and monitoring of heart rate, breathing, and gum color. Oxygen therapy may be used if breathing or oxygenation is a concern. The veterinarian calculates any medication dose from your cat's weight and health, so there is no home dose to follow. ### Monitoring and Blood Work Blood work can check hydration, organ values, and red blood cell oxygen markers. Your veterinarian may repeat exams over several hours to see whether signs are improving or progressing. Most cats with mild gastrointestinal signs improve with supportive care, and the outlook is good when the exposure is small and treated early. ## Outlook After a Cat Eats Hortensia The outlook is generally good for small exposures that cause only vomiting or diarrhea [1][2]. The ASPCA notes that cyanide intoxication is rare, which means most cats do not develop the severe form of poisoning [1][2]. In a large survey of plant poisonings in pets, most exposures caused mild to moderate signs, and fatal outcomes were a minority of reported cases [3]. That said, a large ingestion is different. If your cat ate a lot of leaves or stems, or if signs are severe, the outlook depends on how quickly treatment starts. Cats that receive prompt veterinary care have the best chance of a full recovery. ## Prevention and Safer Alternatives The simplest prevention is to keep hortensia out of your cat's reach. If you grow hydrangeas outdoors, block access with fencing or keep your cat indoors. If you keep cut hydrangeas indoors, place them in a room your cat cannot enter, and never leave vase water where a cat can drink it. If you want cat-safe greenery, choose plants that are listed as non-toxic for cats. You can review [Plants Toxic To Cats](/knowledge/veterinary-medicine/toxicology-and-food-safety/plants-toxic-to-cats) and [House Plants Toxic To Cat](/knowledge/veterinary-medicine/toxicology-and-food-safety/house-plants-toxic-to-cat) before you buy. If flowers are the issue, [Flowers That Are Toxic To Cats](/knowledge/veterinary-medicine/toxicology-and-food-safety/flowers-that-are-toxic-to-cats) covers common bouquet risks. Orchids are a popular alternative, and you can read more in [Are Orchids Toxic To Cats](/knowledge/veterinary-medicine/toxicology-and-food-safety/are-orchids-toxic-to-cats). Other practical steps: - Put hanging baskets and potted hydrangeas on high shelves or in closed rooms. - Pick up fallen petals and leaves promptly. - Teach children and guests not to feed plants to the cat. - Keep the poison control numbers saved in your phone. - If you are unsure whether a plant is safe, assume it is not and keep it away from your cat. ## Limitations and When to Contact a Veterinarian Individual cases need a veterinarian. No article can tell you how much your cat ate, how much toxin was in that plant, or how your cat will respond. Use the guidance below as a triage tool, not a diagnosis. Contact a veterinarian the same day if: - Your cat vomited after chewing hortensia - Your cat has diarrhea, drooling, or reduced appetite - You are not sure how much was eaten - Your cat has a chronic illness, is pregnant, or is very young or very old Go to an emergency clinic now if: - Your cat is weak, wobbly, or cannot stand - Breathing is fast, noisy, or labored - Gums look pale, blue, or bright red - There are tremors, twitching, or seizures - Vomiting will not stop - Your cat is collapsing or unresponsive Schedule a routine visit if your cat had a tiny possible exposure and seems completely normal, but you want peace of mind. Your veterinarian can examine your cat and advise on monitoring. ## Frequently Asked Questions ### Is hortensia the same as hydrangea? Yes. Hortensia is a common name for hydrangea, along with Hills of Snow and Seven Bark [1][2]. Any warning about hydrangea applies to a plant labeled hortensia. ### Are hydrangeas poisonous to cats? Yes, hydrangeas are listed as toxic to cats [1][2]. The plant contains a cyanogenic glycoside, and the usual signs are vomiting, depression, and diarrhea [1][2]. ### Can a cat die from eating hydrangea? Death is uncommon. Cyanide intoxication from hydrangea is rare, and most exposures cause gastrointestinal upset instead [1][2]. A very large ingestion or a cat with other health problems is a bigger concern, so call your veterinarian if you are worried. ### How long do hydrangea poisoning symptoms last in cats? Mild vomiting or diarrhea often settles within a day or two with supportive care. If signs last longer than 24 hours, get worse, or your cat stops eating or drinking, call your veterinarian. ### Should I make my cat throw up after eating hortensia? No. Do not induce vomiting unless a veterinarian tells you to. Call your veterinarian, the ASPCA Animal Poison Control Center at (888) 426-4435, or Pet Poison Helpline at (855) 764-7661 for instructions based on your cat's situation. ## Related Articles - [Are Orchids Toxic To Cats](/knowledge/veterinary-medicine/toxicology-and-food-safety/are-orchids-toxic-to-cats) - [Can Cats Eat Spirulina? Heavy Metal and Algae Safety](/knowledge/veterinary-medicine/toxicology-food-safety/can-cats-eat-spirulina-heavy-metal-and-algae-safety) - [Plants Toxic To Cats](/knowledge/veterinary-medicine/toxicology-and-food-safety/plants-toxic-to-cats) - [Flowers That Are Toxic To Cats](/knowledge/veterinary-medicine/toxicology-and-food-safety/flowers-that-are-toxic-to-cats) - [House Plants Toxic To Cat](/knowledge/veterinary-medicine/toxicology-and-food-safety/house-plants-toxic-to-cat) - [What Plants Can Be Toxic To Cats](/knowledge/veterinary-medicine/toxicology-and-food-safety/what-plants-can-be-toxic-to-cats) - [Are Hydrangeas Toxic to Dogs? Signs and What to Do](/knowledge/veterinary-medicine/toxicology-and-food-safety/hydrangea-toxic-dogs) - [Is Annabelle Hydrangea Toxic to Dogs? Signs and Safety](/knowledge/veterinary-medicine/toxicology-and-food-safety/annabelle-hydrangea-toxic-to-dogs) - [Is Dieffenbachia Toxic to Dogs and Cats?](/knowledge/veterinary-medicine/toxicology-and-food-safety/dieffenbachia-toxic-dogs-cats) ## References 1. [Toxic and Non-toxic Plants: Hortensia](https://www.aspca.org/pet-care/aspca-poison-control/toxic-and-non-toxic-plants/hortensia). ASPCA Animal Poison Control Center. 2. [Toxic and Non-toxic Plants: Hydrangea](https://www.aspca.org/pet-care/aspca-poison-control/toxic-and-non-toxic-plants/hydrangea). ASPCA Animal Poison Control Center. 3. [Plant poisoning in domestic animals: epidemiological data from an Italian survey (2000-2011)](https://pubmed.ncbi.nlm.nih.gov/23716536/). The Veterinary record, 2013. ## Further Reading - [ASPCA Animal Poison Control Center](https://www.aspca.org/pet-care/animal-poison-control) - [ASPCA: People Foods to Avoid Feeding Your Pets](https://www.aspca.org/pet-care/aspca-poison-control/people-foods-avoid-feeding-your-pets) - [U.S. Food and Drug Administration: Potentially Dangerous Items for Your Pet](https://www.fda.gov/animal-veterinary/animal-health-literacy/potentially-dangerous-items-your-pet)