Is Oregano Toxic to Cats and Dogs?
Oregano is toxic to cats, dogs, and horses. The American Society for the Prevention of Cruelty to Animals (ASPCA) identifies the oregano plant as a risk for these animals. This toxicity applies to the fresh plant, a common garden herb also called Greek Oregano.
The scientific name for this plant is Origanum vulgare hirtum, and it belongs to the Lamiaceae family. While the effects of ingestion are generally mild, pet owners should prevent their animals from eating oregano leaves or stems to avoid gastrointestinal upset. The plant contains substances that are known gastrointestinal irritants for pets.
Oregano: what the ASPCA database lists
| ASPCA entry | Oregano |
|---|---|
| Other common names | Greek Oregano |
| Scientific name | Origanum vulgare hirtum |
| Family | Lamiaceae |
| Toxic to | Toxic to Dogs, Toxic to Cats, Toxic to Horses |
| Non-toxic to | None listed |
| Toxic principles | Gastrointestinal irritants |
| Clinical signs listed | Mild vomiting and diarrhea |
Oregano Toxicity in Pets
The ASPCA plant database confirms that oregano is toxic to dogs, cats, and horses. The plant contains gastrointestinal irritants that can cause a reaction if an animal eats it. The primary clinical signs associated with oregano ingestion are mild vomiting and diarrhea. Because the symptoms are usually not severe, pet owners may not immediately connect them to the plant. However, any new or unexplained digestive issues warrant attention.
Oregano in a Home with Pets
Having an oregano plant in a home with pets requires careful management to prevent access. A curious cat or dog that chews on or eats parts of the plant may experience an upset stomach. The severity of the symptoms can depend on how much of the plant the animal consumes. The risk comes from the fresh plant material, which is different from the small amounts of dried herb sometimes used in cooking. Pet food or treats that are professionally formulated to include oregano are not the same as an animal eating the plant directly from a garden or pot. Always read ingredient labels on pet products and introduce any new food to your pet slowly.
Keeping Pets and Oregano Plants Separate
The most effective way to prevent a pet from eating oregano is to make the plant inaccessible. This can be achieved through several simple strategies that create a safer environment for your animals.
- Placement: Keep potted oregano plants on high shelves, in hanging baskets, or in rooms that pets cannot enter. For outdoor gardens, consider using pet-safe fencing or raised garden beds that are too high for dogs to easily reach.
- Supervision: Always supervise pets when they are outdoors or in areas where potentially toxic plants are grown. This allows for immediate intervention if a pet shows interest in chewing on plants.
- Enrichment: Provide plenty of safe toys and activities to keep pets mentally stimulated and physically active. A bored or under-stimulated pet is more likely to chew on inappropriate items, including household plants.
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 an oregano plant, contact your veterinarian or the ASPCA Animal Poison Control Center at (888) 426-4435. A consultation fee may apply. Be prepared to share what part of the plant your pet ate, how much you think they consumed, and when it happened. Even if symptoms seem mild, professional guidance is always recommended for the safety of your pet.
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.