Is cat grass safe? The sources we read treat it as a reasonable thing to offer a cat. Texas A&M's College of Veterinary Medicine describes cat grass as a mix of grasses such as rye, barley, oat and wheat, and quotes a veterinarian saying it "would not be dangerous to have the cat grass freely available." The bigger risk, it says, is a cat confusing cat grass with toxic plants in the home. Catnip is a different case: the ASPCA lists it as toxic to cats because it can cause vomiting and diarrhea. If your cat is unwell after chewing any plant, call your vet or a poison line.
If Your Cat Is Unwell After Chewing a Plant
- Call for advice first. Phone your veterinarian, the nearest 24-hour emergency animal hospital, the ASPCA Animal Poison Control Center at 888-426-4435, or the Pet Poison Helpline at 855-764-7661. Both poison lines answer 24 hours a day, and a consultation fee may apply.
- If there is any chance your cat reached a lily, call now, even if your cat seems fine. Lilies are the plant where waiting costs the most.
- Do not try to make your cat vomit and do not give any home treatment unless a veterinarian or poison-control specialist tells you to.
- Go to an emergency vet immediately if your cat is collapsing, having a seizure, very weak or struggling to breathe.
- Identify the plant. A photo, the pot label or the seed packet helps the person on the phone.
How a plant affects a cat varies with the cat's size and health and with what and how much was eaten. Only a veterinarian can judge that. This article is general information, not a diagnosis.
Is Cat Grass Safe? What the Sources Say
"Cat grass" is not one plant. Texas A&M's College of Veterinary Medicine and Biomedical Sciences, in a 2019 Pet Talk article quoting Dr. Lori Teller, a clinical associate professor there, says: "Cat grass isn't any one type of grass but can be a combination of grasses, such as rye, barley, oat, and wheat."
On safety, the same article gives three points worth knowing.
- Free access is not described as dangerous. Dr. Teller is quoted: "While it would not be dangerous to have the cat grass freely available, if a cat seems to eat it voraciously, then it may be worth consulting with a veterinarian to determine if the cat's diet is meeting all of its nutritional needs."
- Vomiting after eating it is not unexpected. The article gives one theory for why cats eat it: "cat grass is a source of fiber that can either act as a mild laxative or trigger vomiting."
- Confusion with other plants is the real concern. "The bigger concern would be if a cat or other animal confused cat grass with other plants in the home that are potentially toxic."
Cats Protection, the UK cat welfare charity, also suggests offering it: "Provide cat grass for your cat to chew on," and "Plant cat grass and catnip to distract your cat from other plants."
Neither source makes a health claim for cat grass, and this site does not either. The reasons cats eat grass are theories, not established benefits.
Is Catnip Safe for Cats? Why It Is on a Toxic List
This is where most "safe plants for cats" pages go quiet. The ASPCA Animal Poison Control Center lists catnip (Nepeta cataria, also called catswort or catmint) as "Toxic to Cats." It names nepetalactone as the toxic principle, and its clinical signs read: "Many cats love catnip, but it can cause vomiting and diarrhea. It makes some cats sedated and others stimulated."
At the same time, Cats Protection suggests planting catnip to distract cats from other plants. Both statements can be true, and reading them together is the useful part.
- What the ASPCA listing describes is stomach upset and a change in behavior, sedation in some cats and stimulation in others. The entry does not describe organ damage.
- The ASPCA's own plant list explains its mild categories. It describes plants listed "as either non-toxic, or potentially toxic with mild GI upset as their symptoms" as "not expected to be life-threatening to your pets."
- "On a toxic list" does not mean "as dangerous as a lily." The ASPCA's toxic label covers everything from mild stomach upset to kidney failure. Catnip and lilies are both listed; the sources describe very different outcomes.
What this means in practice: catnip is widely offered to cats, but it is not a plant a cat should be left to eat in quantity, and a cat that vomits, has diarrhea or seems unusually sleepy or agitated after eating it should get a call to the vet.
Cat Grass Versus Catnip at a Glance
| Cat grass | Catnip | |
|---|---|---|
| What it is | A mix of grasses such as rye, barley, oat and wheat (Texas A&M) | Nepeta cataria, also called catswort or catmint (ASPCA) |
| ASPCA listing | No single entry, because it is not a single plant | Toxic to cats |
| What the sources describe | May act as a mild laxative or trigger vomiting (Texas A&M theory) | Vomiting and diarrhea; sedation or stimulation (ASPCA) |
| Main caution | A cat used to chewing grass may chew toxic plants too (Texas A&M) | Stomach upset if a cat eats a lot |
| When to call the vet | Eating it voraciously, frequent vomiting, or any sign of illness | Vomiting, diarrhea, or unusual sedation or agitation |
The Real Risk: A Cat That Learns to Chew Green Things
Texas A&M's warning is the one that matters most for a home with plants. A cat given something to chew does not know that the pot of cat grass is allowed and the plant beside it is not.
That is a genuine problem when the plant beside it is a true lily. Cats Protection says "all parts of the lily plant are toxic to cats if ingested, and consuming small amounts can result in severe poisoning," and warns that even a cat with no interest in eating lilies may brush against the pollen and lick it off its fur. Our guide to which lilies are dangerous to cats explains which ones those are.
Some practical points follow from what the sources say.
- Keep cat grass away from other plants. A separate room or a separate shelf makes the allowed plant easier to tell apart.
- Do not keep true lilies in a home with a cat, whether potted or in a bouquet, however much cat grass is on offer.
- Know what else is in the house. If you are not sure whether a houseplant is a problem, our guide on what to do when your cat chewed a houseplant covers how to find out and who to call.
- Grow cat grass from a kit or seed sold for cats, and keep the packet, so you know which grasses are in it if you ever need to tell a vet.
When Grass Eating Is a Reason to Call the Vet
Grass eating on its own is common, but the sources point to a few situations where a call to the vet makes sense.
- Eating it voraciously. Texas A&M suggests this may be worth discussing with a vet to check the cat's diet.
- Frequent vomiting, rather than the occasional episode after chewing grass.
- Diarrhea, lethargy, loss of appetite or any other sign of illness. These are not something a grass pot explains, and a vet should decide what they mean.
- Any chance your cat reached a toxic plant. Signs of plant poisoning can look like ordinary grass-related vomiting, and only a vet or poison line can tell them apart. For how poisoning presents differently in cats, see our guide to cat poisoning and why cats are different.
Sources Checked
On September 27, 2026 we read Texas A&M College of Veterinary Medicine and Biomedical Sciences' Pet Talk article on the basics of cat grass, the ASPCA Animal Poison Control Center's plant entry for catnip and the introduction to its toxic and non-toxic plants list, and Cats Protection's page on plants poisonous to cats.
Frequently Asked Questions
Is cat grass safe for cats to eat every day?
Texas A&M quotes a veterinarian saying it "would not be dangerous" to leave cat grass freely available. If your cat eats it voraciously or vomits often, the same source suggests talking to your vet.
Is it normal for a cat to vomit after eating cat grass?
Texas A&M notes one theory that cat grass is a fiber source that can "trigger vomiting." Frequent vomiting, or vomiting with other signs of illness, is a reason to call your vet.
Is catnip toxic to cats?
The ASPCA lists catnip as toxic to cats, with vomiting, diarrhea, and sedation or stimulation as the signs. The entry does not describe organ damage, but a cat that is unwell after eating catnip should be seen by a vet.
Is catmint the same as catnip?
The ASPCA lists catmint and catswort as other common names for catnip (Nepeta cataria). Common names can be used loosely, so keep the plant label and give it to your vet if your cat is unwell.
Can cat grass stop my cat chewing houseplants?
Cats Protection suggests cat grass and catnip as a distraction, but Texas A&M warns a cat may confuse cat grass with toxic plants. Keeping toxic plants, especially true lilies, out of the home is more reliable than any distraction.
This article is general information and does not replace veterinary care. If you think your cat has eaten a toxic plant, contact your veterinarian, the ASPCA Animal Poison Control Center at 888-426-4435, or the Pet Poison Helpline at 855-764-7661 now. Toxicity varies with your cat's size and health, and only a veterinarian can assess your individual cat.