Vet Warning: This Common Beautiful Flower Could Stop Your Dog’s Heart

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One bite of this flower could stop your dog’s heart. Are you prepared? If your dog just ate Lily of the Valley, stop scrolling. This could be a medical emergency.

As a veterinarian, I’ve seen too many cases where a beautiful garden plant turns into a life-threatening situation. Lily of the Valley may look harmless, but it contains powerful toxins that can seriously affect your dog’s heart. Even a small amount can lead to vomiting, a dangerously slow heartbeat, or worse, cardiac arrest.

In this article, I’ll walk you through why Lily of the Valley is poisonous to dogs, how to recognize symptoms of poisoning, and exactly what steps to take if your pup gets into this plant. You’ll also learn how to prevent future exposure and when it’s time to head straight to the emergency vet. So, let’s make sure your dog stays safe and that you know what to do if things go south.

Warning: If your dog has eaten Lily of the Valley or you suspect they have, stop reading and contact your veterinarian or a 24/7 pet poison hotline immediately. This plant is highly toxic to dogs, and even small amounts can cause serious or life-threatening symptoms. Call your vet or reach out to the ASPCA Animal Poison Control Center at (888) 426-4435 or the Pet Poison Helpline at (855) 764-7661 for immediate guidance.

What Is Lily Of The Valley?

Lily of the Valley, despite its name, is not actually a true lily. It is a perennial flowering plant with tiny bell-shaped flowers and a delicious, sweet scent. They grow to around two feet tall and spread underground, growing from bulbs. Lily of the Valley is a popular garden plant due to its appearance and scent.

The Lily of the Valley can be found in Asia, Europe, and North America. In the U.S., it tends to grow mostly in the Eastern parts, with the states of Pennsylvania, New Hampshire, Virginia, and Vermont having some of the largest numbers. The most common Lily of the Valley species in the USA are:

• C. majalis Albostriata
• C. majalis Berlin Giant
• C. majalis Flore Pleno
• C. majalis Green Tapestry
• C. majalis Rosea

Is Lily Of The Valley Poisonous To Dogs? A Vet Explains

Yes, Lily of the Valley is extremely poisonous to dogs, even in small amounts. This seemingly delicate and fragrant garden flower contains a group of 38 toxins called cardiac glycosides. They are organic compounds that cause the heart to lower its rate of contraction and increase the force of its output. This can disrupt your dog’s heart rhythm and potentially lead to life-threatening symptoms.

Not only are these effects on the heart very dangerous, but the glycosides can also irritate the digestive tract. As a veterinarian, I’ve treated dogs who’ve only taken a few bites of this plant and still needed emergency care. It’s one of those plants that looks harmless but has serious consequences for canine health.

Lily of the Valley also contains saponins, another dangerous compound found in plants that are toxic to dogs. Saponins usually affect your dog’s digestive system, causing irritation that leads to vomiting, diarrhea, and abdominal pain. Saponins can also cause skin irritation.

What Part Of The Lily Of The Valley Plant Is Poisonous To Dogs?

All parts of the Lily of the Valley plant, including the leaves, stems, flowers, and especially the bulbs, are toxic to dogs. Ingestion can cause vomiting, diarrhea, a dangerously slow heart rate (bradycardia), seizures, and, in severe cases, sudden cardiac arrest.

If you’re searching “Is Lily of the Valley poisonous to dogs?” or “Are Lily of the Valley poisonous to dogs?” because your pup may have eaten some, treat it as an emergency. The sooner you act, the better your dog’s chances of a full recovery.

In the following sections, I’ll explain how much is toxic, what symptoms to watch for, and precisely what you should do next, step by step.

Why Is Lily Of The Valley So Dangerous For Dogs?

Lily of the Valley toxicity in dogs is primarily due to its high concentration of cardiac glycosides. When a dog chews or swallows part of the Lily of the Valley plant, these glycosides disrupt the normal electrical signals that control heart rate and rhythm. The result can be bradycardia, arrhythmias (irregular heartbeat), and even heart failure if not treated promptly.

Plus, the toxins don’t just affect the heart; they can also cause:

• Gastrointestinal irritation (vomiting, diarrhea)
• Neurological signs (confusion, weakness, seizures)
• Electrolyte imbalances, which worsen cardiac symptoms

It only takes a small amount of the plant, sometimes just a few bites, for a dog to develop serious symptoms. Puppies and small breeds are especially at risk.

If you suspect your dog has eaten this plant, don’t wait for symptoms to start. Call your veterinarian or a pet poison hotline immediately.

How Much Lily Of The Valley Is Toxic To Dogs?

There’s no exact “safe” amount when it comes to Lily of the Valley. Any ingestion should be treated as potentially dangerous.

Even a small bite of a leaf or flower can be toxic, especially for smaller dogs or puppies. The concentration of cardiac glycosides varies by plant, but it’s impossible to know how potent a particular plant is just by looking at it. That unpredictability makes it more dangerous.

As a vet, I always advise pet owners to err on the side of caution. If your dog chews on, licks, or swallows any part of a Lily of the Valley plant, including the leaves, flowers, stem, or especially the bulb, contact your veterinarian immediately.

Factors that affect how toxic the plant is to your dog include:

• Your dog’s size, age, and overall health
• How much plant material was ingested
• Which part of the plant was eaten
• Whether your dog vomited naturally after eating it

Don’t wait for symptoms to appear. Lily of the Valley toxicity in dogs can escalate quickly, and early treatment is key to preventing serious heart complications.

Signs & Symptoms Of Lily Of The Valley Poisoning In Dogs

The symptoms of Lily of the Valley poisoning tend to start very quickly after ingestion, usually within the first two hours. However, symptoms can appear anytime within 24 hours, so it’s important to keep a close eye on your dog. The symptoms can also vary depending on the amount and which part of the plant or flower your dog has eaten.

The onset of symptoms could be faster or more severe if your dog has eaten the bulb. Common symptoms of Lily of the Valley poisoning in dogs include:

• Vomiting
• Diarrhea
• Lethargy and depression
• Decreased appetite
• Weakness and abnormal gait
• Trembling
• Excessive drooling
• Dilated pupils
• Abnormal heart rate (can be fast or slow) and abnormal heart rhythm
• Seizures
• Collapse

Not all dogs will show the same signs, and severity can escalate quickly. If your dog is showing any combination of vomiting, lethargy, or unusual behavior after eating a plant, and you suspect it could be Lily of the Valley, assume the worst and seek emergency care.

The earlier you act, the better your dog’s chances of recovery. Never wait to “see if it passes”, especially when it involves a cardiac toxin.

How Fast Do Symptoms Appear After Ingestion?

Symptoms of Lily of the Valley poisoning in dogs typically begin within 30 minutes to 2 hours after ingestion. However, the onset can vary depending on the amount consumed, the part of the plant eaten, and your dog’s size and metabolism.

In some cases, dogs may start vomiting or acting lethargic within the first hour. Others may not show obvious signs until the toxin begins to affect the heart, which can take slightly longer. Early action can prevent the toxin from progressing to a more dangerous stage.

Some symptoms, like a slow or irregular heartbeat, may not be visible to you at home but can be detected by your vet using a stethoscope or ECG. That’s why even mild digestive issues after exposure to this plant should be treated seriously.

What Should I Do If My Dog Eats Lily Of The Valley?

If your dog has eaten any part of a Lily of the Valley plant, treat it as a veterinary emergency. Don’t wait for symptoms to start. The whole plant is poisonous, but eating a Lily of the Valley bulb is particularly dangerous as, left untreated, it can cause death within only a couple of hours.

Here’s exactly what to do:

1. Call Your Veterinarian Immediately

Time matters. Contact your primary vet or an emergency animal hospital and let them know what happened. If you can’t reach a local clinic, call a 24/7 pet poison hotline:

• ASPCA Animal Poison Control Center: (888) 426-4435
• Pet Poison Helpline: (855) 764-7661

2. Do Not Try To Induce Vomiting On Your Own

Unless specifically directed by a vet, do not give hydrogen peroxide or induce vomiting. This can sometimes make things worse or cause additional complications.

3. Gather Information For The Vet

If possible, bring a piece of the plant (safely bagged) or take a photo. Knowing exactly what and how much your dog ingested helps guide treatment.

4. Monitor Your Dog Closely

While waiting for care, watch for:

• Vomiting
• Lethargy
• Irregular breathing
• Sudden collapse

If your dog starts showing neurological or cardiac symptoms, head to the emergency vet immediately, even if you haven’t spoken to them yet. Even if your dog seems fine at first, symptoms of Lily of the Valley poisoning can appear suddenly and progress quickly. Early treatment makes all the difference.

How Is Lily Of The Valley Poisoning Diagnosed?

There’s no quick home test for Lily of the Valley poisoning, which is why veterinary diagnosis is so important, especially when dealing with a toxin that can affect the heart.

Here’s how most vets approach the situation:

1. Clinical History

Your vet will start by asking what your dog ate, how much, and when. This is why it’s helpful to bring in the plant (or a photo) if possible. Even if you’re unsure, just saying “I think my dog ate Lily of the Valley” is enough to start treatment protocols. The vet will ask lots of questions about your dog’s symptoms.

2. Physical Examination

They’ll check your dog’s vital signs, including:

• Heart rate and rhythm
• Mucous membrane color
• Respiration
• Neurological responsiveness

Early symptoms can mimic other toxic exposures, so a thorough physical exam is key. Sometimes, the vet will want to perform X-rays or an ultrasound to determine what treatment your dog needs.

3. Electrocardiogram (ECG)

Because cardiac glycosides affect the heart, your vet will want to run an ECG to monitor for arrhythmias or a dangerously slow heart rate (bradycardia). It’s also important for the vet to check your dog’s blood pressure, temperature, and breathing.

4. Bloodwork & Electrolyte Testing

Your dog’s blood may be tested for:

• Electrolyte imbalances (especially potassium)
• Organ function
• Signs of dehydration or shock

Specific blood tests are available to look for the cardiac glycosides found in Lily of the Valley. However, they are very expensive and not always reliable.

The earlier you get to a vet, the easier it is for them to stabilize your dog before the toxin takes full effect. Don’t wait for things to get worse. If you even think your dog ate Lily of the Valley, get help right away.

Treatment: What Happens At The Vet Clinic

Treatment for Lily of the Valley poisoning in dogs focuses on stabilizing the heart, managing symptoms, and preventing the toxin from causing further damage. Since this plant affects the cardiovascular system, early medical intervention can literally save your dog’s life.

Often when dogs eat things they shouldn’t, the vet can give an injection to make them sick to avoid the toxin being absorbed from the stomach. However, with Lily of the Valley, this is not recommended because the toxins are absorbed so quickly after ingestion.

Sometimes it can be useful to clear the stomach using a gastric lavage (washing out the stomach under a general anesthetic) to make sure there are no toxins left. Then, activated charcoal is given to absorb the toxins.

Treatment is mostly supportive, and your dog will probably be hospitalized at the vet for a few days. Supportive treatment includes a fluid drip to help with rehydration and correct electrolyte imbalances, as well as anti-sickness medication, gastroprotectants, and oxygen.

If your dog’s heart has been affected by the poison, they might need medication such as lidocaine or atropine to treat arrhythmias and help get the heart back to normal. The vets will conduct regular blood and urine tests to check your pet’s progress.

There’s no antidote for Lily of the Valley poisoning, but with prompt and aggressive veterinary care, many dogs make a full recovery.

Will My Dog Be Okay If They Ate Lily Of The Valley?

The prognosis for dogs who have eaten Lily of the Valley depends very much on how much of the plant they ate and how quickly they were treated. Generally, you can expect your dog to be home and back to normal after a few days of treatment, as long as they are treated within the first couple of hours after ingestion of the plant.

But your dog will need some essential TLC when they get home from the vet, with a calm, quiet space to rest away from any disturbances. Your dog might need to stay on some medication when they get home. They will need to have a couple of follow-up visits with the vet to make sure they are continuing to make a full recovery.

If you act fast, your dog has a good chance of making a full recovery. The worst outcomes typically occur when treatment is delayed or when pet owners try to manage the situation at home. Don’t hesitate, when it comes to Lily of the Valley, every minute counts.

How Can I Prevent My Dog From Eating Lily Of The Valley?

Prevention is the best way to protect your dog from Lily of the Valley and other toxic plants. Dogs are naturally curious, especially when exploring yards, gardens, or trails. Although many plants in our houses are safe and pet-friendly, some are harmful. So, it’s always best not to encourage them to chew on plants, as they can’t tell the difference between safe and poisonous.

Fortunately, you can take steps to minimize the risk of dogs eating poisonous plants.

1. Remove Lily Of The Valley From Your Yard

If you have Lily of the Valley growing on your property, it’s safest to remove it entirely, roots and all. This plant spreads quickly and can pop up in unexpected places, especially in shaded garden beds.

2. Supervise Outdoor Time

Don’t leave your dog unattended in areas where toxic plants may grow, especially during spring and summer. Keep an eye out during walks, too. Lily of the Valley is common in public gardens and parks.

3. Create A Pet-Safe Garden

If you love gardening, opt for pet-friendly alternatives like marigolds, snapdragons, or sunflowers. Avoid common toxic plants like oleander, foxglove, sago palm, and azaleas. Lily of the Valley is just one of many. Fencing off parts of the garden, especially when pups are young and exploring the world with their mouths, can be helpful too.

If your pup has a habit of tearing up your flower beds, you’re probably wondering why. Usually, this behavior is triggered by boredom, a lack of exercise, or simply just a way of trying to get your attention. You need to make sure that your dog is getting plenty of daily exercise and that they have enough toys for stimulation. If it’s just a naughty habit for your pup, then a bit of training can really help.

4. Train “Leave It” & “Drop It” Commands

These two commands can be lifesaving. If your dog approaches a plant, “Leave it” tells them to back off. If they’ve already picked it up, “Drop it” helps prevent swallowing. To reinforce positive behavior, offer a high-quality reward whenever they head to the flower bed.

5. Know The Warning Signs

Familiarize yourself with the symptoms of poisoning, so you can act quickly if your dog gets into something dangerous.

Being proactive can save you an emergency vet visit, or even your dog’s life. If you’re unsure whether a plant is toxic, check the ASPCA’s list of safe and poisonous plants before planting or allowing access.

Final Thoughts From A Veterinarian

Lily of the Valley is a beautiful plant with a delightful, sweet smell. But it is highly toxic to dogs and one of the most dangerous plants a dog can encounter. So it’s best to avoid growing it in your garden or keep it out of reach if you are a pet parent. Lily of the Valley contains cardiac glycosides, which can have serious and life-threatening effects on your dog’s heart and digestive tract.

If your dog has eaten Lily of the Valley, you need to get your pet seen at the vet as soon as possible, as prompt treatment is key to a good recovery. As a veterinarian, I’ve seen firsthand how fast things can go wrong and how dramatically the outcome improves when pet owners act quickly. The good news is that with prompt care, many dogs make a full recovery.

How To Create A Pet-Safe Backyard

If you want to take your pet’s safety a step further, don’t miss our guide about creating a pet-safe backyard. Start by switching to a pet-safe lawn fertilizer. Many traditional products contain harsh chemicals that can irritate your dog’s paws or cause serious illness if ingested. Consider adding a dog-friendly water fountain to encourage healthy hydration and keep your pup away from stagnant puddles. To prevent wandering and exposure to neighborhood hazards, a GPS-enabled, wireless dog training collar system offers a secure boundary without needing a physical fence.

Has your dog ever had a run-in with a toxic plant? Share your story in the comments below. Your experience could help another pet parent stay prepared.

Why Trust Canine Journal

Dr. Holly Anne Hills is a small animal veterinarian passionate about preventative care and global animal welfare. After graduating from the University of Nottingham, she spent time volunteering in India, where she treated street dogs and gained firsthand experience with toxin-related emergencies, including plant poisonings. Holly now blends her clinical work with writing to help pet owners keep their pets safe. Outside of work, she enjoys bird watching, trail running, and spending time with her own animals.