Last updated: May 4, 2026
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Yes, Mistletoe Is Toxic to Cats
Mistletoe is toxic to cats, and all parts of the plant can cause harm if ingested. The berries, leaves, and stems of both American mistletoe (Phoradendron species) and European mistletoe (Viscum album) contain compounds that irritate the digestive tract and, in larger doses, affect the cardiovascular and nervous systems. During the holiday season, mistletoe is one of the most common plant poisonings that emergency veterinarians see, right alongside poinsettia and holly cases.
The good news is that most cats who nibble on mistletoe show only mild gastrointestinal symptoms. Serious poisoning usually requires consuming a significant amount of plant material, which is uncommon in cats because of their naturally selective eating habits. However, “usually mild” is not the same as “safe.” Even small amounts warrant a call to your veterinarian, and any symptomatic cat should be evaluated promptly.
Severity rating: Moderate. Mild symptoms are typical, but severe cardiovascular and neurological effects are possible with larger ingestions. Always treat mistletoe exposure as an emergency.
The Toxic Compounds in Mistletoe
Mistletoe contains several toxins that work in different ways. The exact mix depends on which species of mistletoe your cat encountered, but the main culprits include:
- Phoratoxin and viscotoxin: Proteins that disrupt cell function and cause cardiovascular effects, including changes in blood pressure and heart rate.
- Lectins: Proteins that can cause severe gastrointestinal irritation and, at high doses, liver and nerve damage.
- Tyramine and other amines: Compounds that affect the nervous system and can trigger neurological symptoms.
European mistletoe is generally considered more toxic than American mistletoe because its concentrations of these compounds are higher, particularly in the leaves and stems rather than the berries. However, both species are dangerous enough that any exposure should be taken seriously.
Clinical Symptoms of Mistletoe Poisoning in Cats
Symptoms usually appear within one to six hours of ingestion. Mild to moderate signs include:
- Vomiting, sometimes repeatedly
- Diarrhea
- Excessive drooling
- Loss of appetite
- Lethargy or hiding behavior
- Abdominal pain
More severe symptoms indicate larger ingestion or individual sensitivity and require immediate emergency care:
- Weakness or collapse
- Difficulty breathing
- Abnormally slow or fast heart rate
- Low blood pressure
- Tremors, staggering, or seizures
- Dilated pupils
- Unconsciousness
Cats are skilled at hiding illness, and early signs of mistletoe poisoning can be subtle. If you know or suspect your cat ate any part of a mistletoe plant, call your vet right away even if your cat seems fine.
What to Do If Your Cat Ate Mistletoe
Time matters with plant poisonings. Follow these steps immediately:
- Remove any remaining plant material from your cat’s mouth and the area around them.
- Identify the species if possible. Photograph the plant and note whether it is American or European mistletoe, and how much was eaten.
- Call your veterinarian or an emergency clinic immediately. Do not wait for symptoms.
- Call the ASPCA Animal Poison Control Center at 888-426-4435 or the Pet Poison Helpline at 855-764-7661 for 24/7 guidance.
- Do not induce vomiting at home. Cats are not dogs, and home remedies can cause more harm than good.
- Keep your cat calm and warm while you arrange transport to the vet.
Bringing a sample of the plant, a photo, or the packaging (if it was store-bought decor) helps the vet confirm identification and choose the right treatment.
Veterinary Treatment for Mistletoe Toxicity
Treatment depends on how much your cat ate and how symptomatic they are. For a small amount with no symptoms, your vet may recommend observation and supportive care. For moderate to severe cases, treatment typically includes:
- Induced vomiting if ingestion was very recent and the cat is stable
- Activated charcoal to bind toxins still in the digestive tract
- IV fluids to support circulation and flush toxins
- Cardiac monitoring for heart rate and blood pressure abnormalities
- Anti-nausea and anti-diarrheal medications
- Seizure control medications if neurological symptoms develop
- Hospitalization for observation, usually 24 to 48 hours
Most cats recover fully with prompt treatment. Delayed care increases the risk of complications, so the key is getting to the vet quickly.
Safer Holiday Decorating With Cats
The safest option is to skip live mistletoe entirely if you have cats. High-quality artificial mistletoe looks nearly identical and poses no risk. If you must display the real thing, consider these precautions:
- Hang it high and out of any climbing path, remembering that cats can jump impressive distances
- Place it in rooms your cat does not access
- Remove any berries that fall to the floor immediately
- Never use it as a centerpiece or table decoration
- Supervise your cat around the decor whenever they are in the room
Mistletoe is one of many plants that can spoil the holidays for pet owners. Poinsettia, holly, amaryllis, lilies, and Christmas cactus all carry varying degrees of risk. Our guides on pine needles and cats and holly berries and dogs cover more holiday plant dangers.
Call Your Vet Immediately If…
Any suspected mistletoe ingestion is a reason to pick up the phone. Do not wait if your cat:
- Ate any amount of mistletoe, confirmed or suspected
- Is vomiting, drooling, or lethargic
- Seems disoriented, weak, or wobbly
- Has difficulty breathing
- Is a kitten, senior, or has existing health problems
For round-the-clock poison advice, the ASPCA Animal Poison Control Center is available at 888-426-4435 and the Pet Poison Helpline at 855-764-7661. Both charge a consultation fee but can be lifesaving. Save these numbers in your phone before the holidays so you are ready if something happens.
Frequently Asked Questions
How many mistletoe berries does it take to harm a cat?
There is no safe number. Even one or two berries can cause symptoms in a small cat or kitten. Larger ingestions, especially of leaves and stems, pose more serious risks.
Is American mistletoe less toxic than European mistletoe?
American mistletoe is generally considered less potent than European mistletoe, but both are toxic enough to cause serious symptoms. The difference is not big enough to treat one as safe.
My cat just licked mistletoe without eating any. Should I worry?
A brief lick without ingestion is unlikely to cause more than mild drooling or a slightly upset stomach. Still, watch for any symptoms for the next 24 hours and call your vet if anything develops.
Can mistletoe kill a cat?
Fatalities from mistletoe are rare but possible, particularly with European mistletoe, large ingestions, or delayed treatment. The cardiovascular and neurological effects can become life-threatening without intervention.
Is artificial mistletoe safe for cats?
Artificial mistletoe is chemically safe, but the small plastic berries and wire stems can cause choking or intestinal obstruction if chewed. Supervise or keep out of reach. For more holiday plant safety, see our guide on rhubarb leaves and cats.
