Is Lily of the Valley Toxic to Cats and Dogs?
Yes, lily of the valley is toxic to cats and dogs. This popular garden plant, known for its delicate, bell-shaped flowers, contains compounds that are dangerous for pets if ingested. All parts of the plant are poisonous, including the leaves, flowers, stems, and roots.
The scientific name for lily of the valley is Convallaria majalis. Its toxicity comes from chemical compounds called cardenolides, including convallarin. These substances can have severe effects on an animal’s body, particularly the heart, making the plant a significant risk to have in or around a home with pets.
Lily of the Valley: what the ASPCA database lists
| ASPCA entry | Lily of the Valley |
|---|---|
| Other common names | None listed |
| Scientific name | Convallaria majalis |
| Family | Asparagaceae |
| Toxic to | Toxic to Dogs, Toxic to Cats, Toxic to Horses |
| Non-toxic to | None listed |
| Toxic principles | Cardenolides (convallarin, and others) |
| Clinical signs listed | Vomiting, irregular heart beat, low blood pressure, disorientation, coma, seizures |
What the ASPCA says about lily of the valley
Lily of the valley (Convallaria majalis) is officially listed as toxic to dogs, cats, and horses. The danger comes from a group of naturally occurring poisons known as cardenolides. These substances are present throughout the entire plant.
If a pet ingests any part of the lily of the valley plant, it can lead to a range of serious clinical signs. Potential symptoms of poisoning include:
- Vomiting
- Irregular heart beat
- Low blood pressure
- Disorientation
- Coma
- Seizures
The symptoms related to the heart are particularly concerning. An irregular heartbeat and a drop in blood pressure are medical emergencies that require immediate professional care. The severity of the symptoms can depend on how much of the plant the animal consumed.
What this means for pet owners
For households with pets, the toxicity of lily of the valley means that this plant poses a serious safety risk. Because all parts of the plant are poisonous, even a curious nibble on a leaf or flower can be harmful. The risk extends to the water in a vase holding cut lily of the valley flowers, as the toxic cardenolides can leach into it. A pet drinking this water could be poisoned.
Cats and dogs often explore their environment with their mouths, and they may chew on plants out of boredom, curiosity, or instinct. Given the potential for severe symptoms from even a small amount of this plant, it is not a safe choice for homes or gardens where pets have unsupervised access. It is important for pet owners to be able to identify lily of the valley to prevent accidental ingestion.
Keeping cats and dogs and this plant apart
The most effective way to prevent lily of the valley poisoning is to ensure pets cannot access the plant. This means not keeping it as a houseplant and removing it from any garden areas where your dog or cat plays. If the plant is in a neighbor’s yard, make sure your fencing is secure to keep your pet from wandering.
When walking your dog, be mindful of the plants along your route and prevent your dog from eating any unfamiliar vegetation. Supervise pets closely when they are outdoors. If you receive a floral bouquet containing lily of the valley, the safest course of action is to place it in a room that is completely inaccessible to your pets or to remove the toxic flowers from the arrangement. Always read labels on any new plants you bring into your home to confirm they are non-toxic to animals.
When to call your vet
If your pet chewed or ate part of this plant, call your veterinarian or an animal poison control line. Note which plant and which part, how much may be gone and when, and take a photo or a piece of the plant with you.
If you suspect your pet has eaten any part of a lily of the valley plant, contact your veterinarian or an animal poison control hotline immediately. The ASPCA Animal Poison Control Center can be reached at (888) 426-4435, though a consultation fee may apply. Note the time of ingestion and how much you think your pet consumed. Do not wait for symptoms to appear, as prompt medical attention is critical.
Emergency signs: go now
- Collapse, fainting or severe weakness
- Seizures, tremors or trouble standing
- Trouble breathing or blue, gray or very pale gums
- Repeated vomiting or retching, or a swollen, painful belly
- Any known contact with a substance listed as toxic, even before signs appear
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- Vomiting or diarrhea that lasts or keeps coming back
- Not eating or drinking, or drinking much more than usual
- Drooling, pawing at the mouth or a swollen face
- Lethargy, hiding or acting unlike themselves
ASPCA Animal Poison Control Center: (888) 426-4435 (a consultation fee may apply). Your own vet or nearest emergency clinic is always a good first call.
Sources
Last checked October 21, 2026. Listings and guidance can change; your veterinarian knows your pet’s health history.