Center for Companion Animal Health

Daylilies.  All plants in family liliaceae are toxic to pets.
Day Lillies

Pets and Toxic Plants

A surprisingly large number of common garden and household plants are toxic to pets, and reactions to toxicity range from mild to life-threatening. Pets, like young children, explore the world with their senses, and they are therefore vulnerable to accidental poisoning.  Many of these plants make wonderful additions to the  garden, but it is important to know which plants are toxic.  If possible, avoid planting these where pets (or children) will have frequent unsupervised access to the plants. 

The 12 plants listed below are responsible for the majority of calls to our Veterinary Medical Teaching Hospital (VMTH) about possible plant poisoning. The list was compiled by Director of Pharmacy Dr. Valerie Wiebe. The toxicity of the plants below varies according to the species of animal exposed (cat, dog, bird, etc.), the amount of the plant that was ingested, and  the specific variety or species of the plant. 

If you suspect your pet has ingested any of the plants below, call your veterinarian immediately.  Do not wait to see if symptoms appear, because in some cases of poisoning, by the time symptoms appear it is too late to save the animal. 

  1. Lilies (Lilium, all spp.): Ingesting any part of the plant can cause complete kidney failure in 36-72 hours. First symptoms appear in a few hours and may include appetite suppression, lethargy, vomiting.  Cats are especially sensitive to lily poisoning, so be very careful to keep your cats away from liliies of any kind, including the Amaryllis, Easter lilies, and Stargazer lilies so often found in homes around the holidays.
  2. Lily of the Valley (Convallaria majalis): Ingesting any part of the plant can cause cardiac dysrhythmias, vomiting, diarrhea, confusion, weakness, and even death. (Photo courtesy of freebigpictures.com web site).
  3. Anemone (Anenome and Pulsatilla, family Ranunculaceae): Irritating to the mucus membranes, and can cause blisters, hemorrhagic gastritis, shock, convulsions, and death. (Photo is Japanese Anemone).
  4. Aloe Vera (family Liliaceae): Vomiting, depression, diarrhea, anorexia, tremors, change in urine color.
  5. Amaryllis (family Amaryllidaceaea, incl. Hippeastrum spp.) All species, including Belladonna Lily, are toxic, and especially dangerous to cats. The bulbs are the toxic part of the plant.  The "Amaryllis" commonly seen during the December holidays are Hippeastrum species.  Symptoms include vomiting, depression, diarrhea, abdominal pain, hyper-salivation, anorexia, tremors.  (Photo courtesy of Ellen Zagory, UC Davis Arboretum).
  6. Asparagus Fern (family Liliaceae): Allergic dermatitis, gastric upset, vomiting, diarrhea.
  7. Daffodil (Narcissus): Vomiting, diarrhea. Large ingestions cause convulsions, low blood pressure, tremors, cardiac arrhythmias.
  8. Philodendrons: Irritation, intense burning and irritation of the mouth, lips, tongue, excessive drooling, vomiting, difficulty swallowing.
  9. Jade Plants (Crassula argentea): Vomiting, depressions, ataxia, slow heart rate.
  10. Chrysanthemums: Vomiting, diarrhea, hyper salivation, incoordination, dermatitis.
  11. Cyclamen (Cyclamen persicum): The tubers or rhizomes contain the toxic glycoside cyclanin, a terpenoid saponin.  Ingestion can cause excess salivation, vomiting, diarrhea, heart rhythm abnormalities, seizures, or even death in rare cases.
  12. Cycads (including Sago palm; cardboard palm; etc.): The "Sago palm" is a cycad, not a true palm, and all parts of the plant are poisonous. Symptoms include vomiting, lethargy, melena (black "tarry" feces), icterus (jaundice), increased thirst, hemorrhagic gastritis, bruising, coagulopathy, liver failure, and death.  A northern California police dog, a patient at one of our Companion Animal Memorial Fund donor clinics, died in November 2011 after ingesting parts of this plant.

Common plants that are highly toxic but only rarely ingested by pets include:

(Note on photos:  Not all plants have photos posted, either because they were not in bloom, or a good example with positive identification has not yet been located.  Pictures will be added as they become available).

Toxic Plants Demonstration Garden at UC Davis School of Veterinary Medicine

If you are able to visit the UC Davis campus, there is a Toxic Plants demonstration garden  (just north of "Vet Med 3A" and south of Tupper Hall) which includes many plants commonly grown in northern California which are known to be toxic to pets. 

Additional Resources

There are many resources available for information about plant toxicity, but only a few provide information specific to companion animals. Among the most useful are the following:

Bibliography (abbreviated):

A Guide to Plant Poisoning of Animals in North America by Anthony P. Knight and Richard G. Walter 
Teton NewMedia, 2001. (Geared toward livestock and grazing animals).

The North American Guide to Common Poisonous Plants and Mushrooms by Nancy J. Turner and Patrick von Aderkas
Timber Press, Inc., 2009.

Handbook of Poisonous and Injurious Plants, 2nd edition, by Lewis S. Nelson, M.D.; Richard D. Shih, M.D., and Michael J. Balick, Ph.D.
The New York Botanical Garden, 2007.  (Useful color photos for identification.  This edition is an update of the 1985 edition of the AMA Handbook of Poisonous and Injurious Plants).

Poisonous Plants of California by Thomas C. Fuller and Elizabeth McClintock 
University of California Press, 1986.

Toxic Plants Dangerous to Humans and Animals, Jen Bruneton, translated from the French original by Caroline K. Hatton 
Lavoisier Publishing Inc. or Intercept Ltd., 1999. (Descriptive text for entires includes which animal species are affected )

Toxicity of Houseplants by David G. Spoerke, Jr. and Susan C. Smolinske  
CRC Press, 1990