# Is Mistletoe Poisonous to Dogs? Signs and Risks Is mistletoe poisonous to dogs? Yes. Both the American and European types are toxic to dogs, and eating even a small amount of the plant or its berries can cause vomiting, diarrhea, and other problems [1]. The risk goes up during the holidays, when sprigs of mistletoe come into the house for decorating. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - American mistletoe (Phoradendron flavescens) is listed as toxic to dogs, cats, and horses by the ASPCA Animal Poison Control Center [1]. - The berries are the most dangerous part because they contain the highest concentration of toxins, but the leaves and stems are toxic too [1]. - Dried mistletoe does not become safe. Drying does not remove the toxic compounds, so a sprig saved from last year is still a hazard. - If your dog ate mistletoe, call your veterinarian, the ASPCA Animal Poison Control Center at (888) 426-4435, or Pet Poison Helpline at (855) 764-7661 right away. - Do not make your dog vomit unless a veterinarian tells you to. ## Is Mistletoe Toxic to Dogs? Yes, mistletoe is toxic to dogs. The ASPCA Animal Poison Control Center lists American mistletoe, scientific name Phoradendron flavescens, as toxic to dogs, cats, and horses [1]. The plant belongs to the family Viscaceae, and every part of it carries the toxic principle [1]. There are two main types of mistletoe you might bring home, and both matter for dog safety. ### American Mistletoe vs. European Mistletoe American mistletoe (Phoradendron flavescens) is the plant most often sold in the United States for holiday decorating [1]. European mistletoe (Viscum album) is more common in Europe but also appears in some products and supplements sold here. The ASPCA record covers American mistletoe directly and names its toxic principles as toxalbumin and pharatoxin viscumin, which fall into the lectin and phoratoxin families [1]. European mistletoe contains lectins and viscotoxins, compounds that researchers have studied for their effects on cells [2]. Those same compounds are part of why the plant is a problem when a dog eats it. For a broader look at holiday and household plants that can harm dogs, see [Plants Poisonous To Dogs](/knowledge/veterinary-medicine/toxicology-and-food-safety/plants-poisonous-to-dogs). ### Which Parts Are Most Toxic? The berries are the biggest concern. They contain the highest concentration of the toxic compounds, and they are small, round, and pale, which makes them easy for a dog to snap up off the floor [1]. A dropped berry during decorating is a common way dogs get exposed. The leaves and stems are also toxic [1]. A dog who chews on a hanging sprig is eating leaves and stem material, not just berries, so any part of the plant counts as an exposure. ### Is Dried Mistletoe Poisonous to Dogs? Yes, dried mistletoe is still poisonous. Drying the plant does not destroy the lectins and phoratoxins that make it toxic [1]. A dried sprig kept in a box from last December carries the same risk as a fresh one. If you store holiday decorations, keep mistletoe out of reach or throw it away. ### What About Mistletoe Supplements and Extracts? You may see mistletoe extracts sold for human or veterinary use. These are concentrated preparations studied in cancer research, including work with dogs [2][3]. They are not the same thing as a plant in your house, and they are given under supervision at controlled amounts. Do not give your dog any mistletoe product on your own. A veterinarian calculates the dose from the pet's weight and health, and the wrong amount of a concentrated extract can cause harm. ## What Makes Mistletoe Poisonous? The toxic compounds in American mistletoe are toxalbumin and pharatoxin viscumin, which belong to the lectin and phoratoxin groups [1]. These are the substances that cause the clinical signs veterinarians see after a dog eats the plant. Lectins and viscotoxins are also found in European mistletoe, and researchers have documented their effects on cells, including anti-proliferative activity [2]. In a poisoning situation, the concern is different. When a dog eats a large amount of plant material, these compounds irritate the gut and can affect the body more broadly. The ASPCA lists the expected effects of American mistletoe as vomiting, diarrhea, low blood pressure (rare), difficulty breathing, and a low heart rate [1]. The low blood pressure and heart rate effects are uncommon, but they are the reason a serious exposure needs veterinary care instead of watching at home. One study on a mistletoe extract in hypertensive dogs found a gradual blood pressure-lowering effect that lasted a long time, with a dose-effect relationship across a range of doses [4]. That was a controlled extract given in a research setting, not a dog eating a sprig of holiday decor, but it supports the idea that mistletoe compounds can affect blood pressure and circulation. ## Signs Your Dog Ate Mistletoe Signs usually show up within a few hours of eating the plant. The most common are stomach upset, and they can range from mild to severe depending on how much your dog ate and which parts. Watch for: - Vomiting [1] - Diarrhea [1] - Drooling or lip smacking (common after eating plant material) - Pawing at the mouth or acting uncomfortable - Difficulty breathing [1] - Weakness, wobbliness, or collapse - A slow heart rate [1] - Low blood pressure, which is rare [1] ### Typical Timeline Vomiting and diarrhea often start within a few hours. Breathing difficulty, a low heart rate, and low blood pressure are less common and tend to appear with larger exposures [1]. If your dog ate berries, assume the exposure is more serious than if they chewed a leaf, because berries carry the highest toxin concentration [1]. Some dogs eat plant material and show no signs at all. That does not mean the plant is safe. It means the amount or the part eaten was not enough to trigger visible effects. A veterinarian can help you decide whether monitoring at home is reasonable or whether treatment is needed. ## What to Do Right Now If you think your dog ate mistletoe, act the same day. Do not wait for signs to appear. 1. Move your dog away from the plant and pick up any remaining berries, leaves, or stems so they cannot eat more. 2. Call your veterinarian, the ASPCA Animal Poison Control Center at (888) 426-4435, or Pet Poison Helpline at (855) 764-7661. 3. Tell them what part was eaten, roughly how much, and when it happened. If you are not sure, say so. They can still help. 4. Do not induce vomiting unless a veterinarian tells you to. Making a dog vomit when it is not safe can cause more harm than good. 5. Keep the plant or a photo of it handy so you can describe it accurately. If your dog is having trouble breathing, is collapsing, or has a very slow heart rate, treat it as an emergency and go to the nearest veterinary hospital now [1]. ## How Veterinarians Treat Mistletoe Poisoning Treatment depends on how much your dog ate, when they ate it, and what signs they are showing. A veterinarian will start with a physical exam and questions about the exposure. Common steps include: - Decontamination. If the exposure was recent and your dog is stable, a veterinarian may induce vomiting or give activated charcoal. This is a decision made by the vet, not at home. - Supportive care. Fluids, medication for nausea, and a quiet place to recover are often enough for mild cases. - Monitoring. Dogs with breathing difficulty, a low heart rate, or low blood pressure need close monitoring and possibly more intensive care [1]. - Blood work. Your veterinarian may run tests to check organ function and make sure your dog is stable. Most dogs who eat a small amount and get care early do well. Dogs with heavy berry exposure or underlying health problems need more support. ## Outlook After Eating Mistletoe The outlook is generally good when the exposure is small and treatment starts early. Vomiting and diarrhea usually settle with supportive care. The cases that worry veterinarians are the ones with breathing trouble, a slow heart rate, or low blood pressure [1]. These signs are rare, but they mean the dog needs immediate care. If your dog is showing any of them, do not wait to see if things improve on their own. ## Preventing Mistletoe Exposure Prevention is simple once you know where the risk lives. - Skip real mistletoe. Use a fake sprig or a different decoration. If you want a plant that is safe around dogs, ask your veterinarian or check a reliable toxic plant list before you buy. - Hang it high. If you do keep real mistletoe, hang it well above a dog's reach and never leave it on a table or floor. - Clean up immediately. Pick up fallen berries and leaves right away. Berries are the most toxic part [1]. - Watch the gifts. Mistletoe sometimes arrives tucked into gift baskets or wreaths. Check before you set them down. - Store carefully. Dried mistletoe stays toxic, so do not keep old sprigs in a box your dog can get into [1]. If your dog has a habit of eating plants, review your whole home for hazards. Our guide to [Plants Poisonous To Dogs](/knowledge/veterinary-medicine/toxicology-and-food-safety/plants-poisonous-to-dogs) covers common ones. Other holiday and household items matter too, including foods like [Can Dogs Eat Plums? Toxicity Warnings & Pit Risks](/knowledge/veterinary-medicine/toxicology-food-safety/can-dogs-eat-plums-toxicity-warnings-pit-risks). ## Limitations and When to Contact a Veterinarian This article gives general information. Every case is different, and your dog's individual situation needs a veterinarian who can examine them and ask about the exposure. Contact a veterinarian the same day if: - You saw your dog eat mistletoe, even a small amount - You are not sure how much was eaten - Your dog is vomiting or has diarrhea - Your dog seems uncomfortable, drools, or paws at the mouth Go to an emergency clinic now if: - Your dog is having trouble breathing [1] - Your dog collapses or cannot stand - Your dog's heart rate seems very slow [1] - Your dog's gums look pale - Signs are getting worse instead of better Schedule a routine visit if your dog ate a tiny amount days ago, has no signs, and you want a checkup for peace of mind. ## Frequently Asked Questions ### Is mistletoe dangerous to dogs? Yes, mistletoe is dangerous to dogs. American mistletoe is listed as toxic to dogs, and eating the plant can cause vomiting, diarrhea, and in rare cases breathing trouble and a low heart rate [1]. The level of danger depends on how much was eaten and which parts. ### Are mistletoe berries poisonous to dogs? Yes, the berries are the most toxic part of the plant. They hold the highest concentration of the toxic compounds, and their small size makes them easy for a dog to swallow [1]. If your dog ate berries, call a veterinarian or poison control right away. ### Are mistletoe leaves toxic to dogs? Yes, the leaves are toxic too. The ASPCA lists the whole plant as toxic, not just the berries [1]. A dog who chews on a hanging sprig is eating leaves and stems, so treat that as an exposure. ### Is dried mistletoe poisonous to dogs? Yes, dried mistletoe is still poisonous. Drying does not remove the toxic compounds, so an old sprig from last season is just as risky as a fresh one [1]. Throw away or safely store any dried mistletoe in your home. ### Is mistletoe harmful to dogs in small amounts? Even small amounts can cause stomach upset, and the risk is higher with berries. Because the amount needed to cause signs varies by dog, call your veterinarian or a poison control line for guidance instead of guessing. Do not wait for signs to appear before you ask for help. ## Related Articles - [Are Tarantulas Poisonous to Dogs? Understanding the Risks](/knowledge/veterinary-medicine/pet-care/are-tarantulas-poisonous-to-dogs-understanding-the-risks) - [Plants Poisonous To Dogs](/knowledge/veterinary-medicine/toxicology-and-food-safety/plants-poisonous-to-dogs) - [Can Dogs Eat Plums? Toxicity Warnings & Pit Risks](/knowledge/veterinary-medicine/toxicology-food-safety/can-dogs-eat-plums-toxicity-warnings-pit-risks) - [Are Tarantulas Dangerous to Dogs?](/knowledge/veterinary-medicine/pet-care/are-tarantulas-dangerous-to-dogs) - [My Dog Ate a Frog: Is It Poisonous?](/knowledge/veterinary-medicine/vet-visit-decisions/dog-ate-frog-poisonous) - [Dog Ate a Candle: Wax, Wicks, and Fragrance Risks Explained](/knowledge/veterinary-medicine/emergency-and-first-aid/dog-ate-candle-risks) - [Is Mistletoe Cactus Toxic to Dogs? Safety Facts](/knowledge/veterinary-medicine/toxicology-and-food-safety/mistletoe-cactus-toxic-dogs) - [Is Mistletoe Toxic to Cats? Real vs Cactus Varieties](/knowledge/veterinary-medicine/toxicology-and-food-safety/mistletoe-toxic-cats) - [Is Holly Poisonous to Dogs? Types and Toxicity](/knowledge/veterinary-medicine/toxicology-and-food-safety/holly-poisonous-dogs) ## References 1. [Toxic and Non-toxic Plants: Mistletoe "American"](https://www.aspca.org/pet-care/aspca-poison-control/toxic-and-non-toxic-plants/mistletoe-american). ASPCA Animal Poison Control Center. 2. [Viscum album (mistletoe) extract for dogs with cancer?](https://pubmed.ncbi.nlm.nih.gov/38234984/). Frontiers in veterinary science, 2023. 3. [Viscum album L., a Therapeutic Option for Neoplastic Diseases in Companion Animals? A Systematic Review](https://pubmed.ncbi.nlm.nih.gov/35810741/). Complementary medicine research, 2022. 4. [Study on the mechanism of compound mistletoe fluidextract in relieving hypertension](https://pubmed.ncbi.nlm.nih.gov/20112493/). Journal of traditional Chinese medicine = Chung i tsa chih ying wen pan, 2009. ## 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)