Common Plant Toxicities

I was weeding my garden today, and I realized that there are a lot of common plants which I see as toxicities in Emergency situations.  I thought I would do the top 5 that I see; then mention a few really toxic plants, which I would not have around my kids or my pets.

1.   Mushrooms.  Ok, some are okay, but there are 4 different types of toxins associated with them, and I have seen animals affected by them. Clinical signs vary by type but all start with vomiting and abdominal pain, then can exhibit drooling, tremors, wheezing, slow heart rate. Neurologic signs can include hallucinations, high heart rate and fever. Some will cause bloody diarrhea.  Some animals are found dead; so, they can be very serious.

2.   Lilies.  This includes anything in the family Lilium or Hemerocallis: Tiger Lily, DayLily, Asiatic Hybrid, Easter Lily, Japanese Show, Rubrum, Stargazer, Red, Western and Wood Lilies. They are ALL highly poisonous to cats. The entire plant is toxic, pollen, leaves, petals and even the water they are in can kill. Ingestion of this will result in severe, acute kidney failure.

3.  Lily of the Valley, Foxglove, Oleander, Milkweed, Kalanchoe, Dogbane, Star of Bethlehem. This affects both cats and dogs, and cause life threatening heart irregularities, or death. Signs include drooling, nausea, vomiting, irregular heart rate, weakness, collapse, dilated pupils, tremors, seizures and death. All parts of the plants are poisonous, even the water in the vase.

4.  Rhododendrons, Azaleas. These are common plants which, when ingested, disrupt the skeletal and heart muscle function. The entire plant is poisonous, and as little as 0.2% of an animal’s body weight can result in poisoning. This would be 20 g, or less than an ounce, for a 10kg/22 lb. dog. Signs include drooling, vomiting, diarrhea, not wanting to eat, abdominal pain, irregular heart rate, low blood pressure, weakness, tremors; all the way to blindness, seizures, coma or death.

5.  Daffodils, Tulips or Hyacinths. The bulb is the most toxic part here, and will cause irritation in the mouth, vomiting, drooling and often diarrhea. Large ingestions especially of daffodils will cause more severe symptoms, so if you see your pet chewing on these, call us immediately.


Plants I will not have near my pets or my family

1.  Yew. This evergreen bush is so toxic that it kills all species that eat it. One form of it was the basis of a common chemotherapy drug, Taxol or Taxotere. The plant will cause drooling, vomiting, weakness, difficulty breathing, life-threatening changes in heart rate and blood pressure, dilated pupils, tremors, seizures, coma and death. The entire plant is toxic, especially the berries, where as little as one berry could kill a Chihuahua.

2.  Castor Beans, also African Wonder Tree. The bean of this plant contains ricin, which is so toxic that even a little can cause death. Inappetance, drooling, abdominal pain, and vomiting.

3.  Sago Palm. While not indigenous to this area, I have seen them for sale as house plants even at Home Depot. The entire plant is toxic, with the seeds/nuts being the most toxic. Clinical signs can start within 15 minutes of ingestion with vomiting and diarrhea, and will progress to severe liver failure in 2-3 days. Survival rate is about 50% even with aggressive treatment.

4.  Autumn crocus. This is a fall blooming plant of the family Colchicum, is also known as Meadow Saffron or Naked Lady. It causes drooling, vomiting, GI bleeding, bloody diarrhea, liver and kidney damage, respiratory failure, CNS signs and potentially death.


As you have likely noticed, a lot of the plants cause similar clinical signs at first. Getting to us immediately for treatment could be the difference between life and death. The name of the plant is always helpful as well, so we can plan for the best treatment in each case.

For further information on poisonous plants, has excellent information and pictures on their site.