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Are Poinsettias Poisonous: What Plants Are Toxic to Cats?

The colorful holiday plant has an infamous reputation. But how dangerous are poinsettias, and what plants are actually toxic to cats?

By Stephen C. George
Dec 13, 2023 2:00 PMDec 15, 2023 5:55 PM
Cat with poinsettia
Cat with poinsettia. Cozy Christmas background. (Credit: AnnHirna/Shutterstock)


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‘Tis the season of plant-related traditions: Putting up a tree, decking the halls with boughs of holly, hanging mistletoe — and slandering the good name of the innocent poinsettia.

Almost everyone reading this has heard some variation of the statement or possibly even said it themselves: “You know, poinsettias are poisonous. Don’t leave that plant where your cat/dog/kid can get at it.” Next to children, cats in particular seem to be the family members people worry most about, probably because our feline pals are infamous nibblers of houseplants.

No one is entirely sure why that is, incidentally — cats have never held a press conference on the matter — but some common-sense explanations are that kitties may chew on plants in order to get some fiber to aid digestion (and ease the passage of hairballs), or possibly to seek out nutrients that they might otherwise lack in their diet. It could also be that they just like the taste of green and leafy things. Or, as many owners would be willing to assert, cats may eat plants simply because they know it bugs the bejesus out of you.

Regardless, as seasonal myths go, passing poinsettia warnings along may not exactly be a joyous tradition, but it sure is an enduring one. For more than a century, we’ve been spreading this bit of horticultural gossip amongst one another without really bothering to check the facts.

Are poinsettias anything you want to feed your cat or anyone else in your house? Absolutely not. But they are hardly dreaded plants of doom, as so many of us have been brought up to believe. Here’s what the science says about poinsettias and their alleged perils. 

What Is a Poinsettia?

Greenhouse with hundreds of flowering poinsettia plants. (Credit: Tammi Mild/Shutterstock)

Also known as Euphorbia pulcherrima, poinsettias are part of the spurge family, which includes a diverse array of plants, such as the rubber tree and the castor oil plant, to name just two.

Who Is the Poinsettia Named After?

We know the plant by the name poinsettia thanks to a 19th-century American diplomat named Joel Poinsett, who was the first U.S. ambassador to Mexico in 1825.

According to the Library of Congress, it was during this appointment in 1828 that Poinsett first encountered the colorful plant that would bear his name. When he returned to the U.S., he brought samples back with him. Today, the USDA says that poinsettias are the #1 potted plant in America, a $250-million-per-year business that sees about 80 million poinsettias sold every season.

Is a Poinsettia a Flower?

Poinsettias are not flowers but shrubs — the colorful leaves that look like flowers are known as bracts. Like rubber trees, poinsettias exude a natural latex sap — a milky fluid that can seep out when parts of the plant are torn or broken. Over the decades, some people, including scientists and public health officials, would maintain that this fluid and the bracts themselves can deliver a hefty — and possibly fatal — jolt of poison to any cat, dog, or person foolish enough to sample them.

Read More: Evolutionary Quirks Helped Poinsettias Rule the Holidays

Are Poinsettias Toxic?

1916 catalog illustration of a poinsettia. (Credit: Public domain/Wikimedia Commons)

The short answer is: No. Several sources agree that the rumors of poinsettia peril likely originated more than a century ago when the respected botanist Joseph Francis Rock published a paper in 1920 on poisonous plants.

The Origin of the Poinsettia Myth

To underscore the alleged danger of the poinsettia, Rock claimed that, a year earlier, a child had been found dead next to a poinsettia plant after supposedly consuming parts of it. Although that story has never been verified, it would be repeated in future works by other scientists as “proof” of the poinsettia’s poisonous nature.

Debunking the Poinsettia Myth

It wasn’t until the early 1970s that researchers at Ohio State University decided to test the rumor by feeding poinsettias to rats. Not a single lab animal died in the study or even got appreciably sick. Later, a 1996 review of nearly 23,000 poinsettia-related poison-control cases revealed no human fatalities among those thousands of instances. Having said that, the sap of the poinsettia has been known to cause an irritating skin rash, and there is a chance that someone with a latex allergy could experience more severe symptoms if exposed to the milky fluid.

Are Poinsettias Toxic to Cats?

Still, you wouldn’t want your cat or any other member of your family to eat any part of the plant. While not poisonous per se, poinsettia leaves are reportedly unpleasant to eat and would likely cause stomach irritation, possibly giving the eater nausea, vomiting, and diarrhea. So, just don’t do it.

For the record, estimates say that a person would need to eat up to 500 or so leaves to get really sick on poinsettias. But then, eating 500 or so leaves of any plant in one sitting, even ones we normally enjoy in salads, would probably be enough to make anyone queasy. And that assumes that an individual person (or pet) could stand to stomach the plant at all, which is highly unlikely in the case of poinsettias. Their leaves are exceedingly bitter, to the point that almost no one with a sense of smell or taste would willingly consume them, including your cat. 

Read More: 5 Medicines Derived from Poisons 

What Plants Are Toxic to Cats?

Cat playing with poinsettia. (Credit: Jay Ondreicka/Shutterstock)

Meanwhile, there are plenty of genuinely poisonous plants that could be harmful or fatal to your cat if they decide to take a nibble. Here are just a few of the most common plants to watch out for.


(Credit: Berliner Art/Shutterstock)

Are Lilies Toxic to Cats?

Lovely but lethal, many lilies — including Easter lilies, tiger lilies, daylilies and more — are especially toxic to cats. Eating even a small amount could cause kidney failure, killing your kitty in a deeply uncomfortable and wretched manner. Symptoms — which include vomiting, drooling, diarrhea, and general lethargy — can show up within a couple of hours of exposure, so if you think your cat has nibbled on a lily, get them to the vet immediately. (Many but not all lilies can also be toxic to dogs and people, but apparently far less so than they are to cats.)


(Credit: Natali9701/Shutterstock)

Are Daffodils Toxic to Cats?

Poisonous but only rarely fatal, eating any part of the daffodil plant is nevertheless a bad idea for your cat. In addition to the above symptoms, shivering, seizures, and difficulty breathing are all signs of daffodil poisoning, which should require immediate veterinary attention. FYI, daffodils are part of the Amaryllidaceae family, which include the Amaryllis, another plant sometimes associated with the holidays but which is also toxic to cats (as well as dogs).


(Credit: Piskova Photo/Shutterstock)

Are Dieffenbachia Toxic to Cats?

Another popular houseplant, the dieffenbachia is toxic to all pets, and their humans, too. You may have heard that dieffenbachia is known by another name: dumb cane. That’s because the main symptoms caused by ingesting the sap of the plant are burning and swelling of the tongue and throat, making speech difficult. Unfortunately, if the swelling is bad enough, it can also make breathing difficult, sometimes fatally so.  

For a much more comprehensive list of plants that could be dangerous to your cat, dog, or other family members, check out the ASPCA’s guide to both toxic and non-toxic plants. You can also call the ASPCA’s Animal Poison Control Center, 24 hours a day, at (888) 426-4435. 

 Read More: Have Yourself a Toxic Berry Christmas

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