Winter Holiday Plants

Laurie Anne Walden, DVM

Yew is highly toxic to animals and people.

Some decorative winter holiday plants pose risks to pets. Other plants that aren’t actually toxic can still cause upset stomach if an animal swallows them.
 
If you think your pet might have swallowed or been exposed to a toxic plant, contact your veterinarian, an animal emergency clinic, or a 24-hour animal poison control hotline (a fee may apply):

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

 
Amaryllis (Amaryllis species)
Ingestion of amaryllis leaves, stems, or bulbs can cause drooling, vomiting, diarrhea, belly pain, lethargy, and a drop in blood pressure.
 
Christmas cactus (Schlumbergera species)
Christmas cactus isn’t toxic. However, an animal that swallows part of one might vomit or have diarrhea.
 
Christmas rose, hellebore (Helleborus niger)
Hellebores contain cardiac glycosides, compounds that affect heart function. Ingestion of any part of the plant can cause drooling, belly pain, vomiting, diarrhea, and lethargy.
 
Christmas trees
The Christmas trees most commonly grown in North Carolina (firs, pines, cedars, and cypress) aren’t toxic, although like other non-food plants they could cause vomiting or intestinal blockage if an animal swallowed enough of one. The risks to pets are from trees falling, ornaments breaking, exposure to electrical cords, and possibly exposure to preservatives (which are not very toxic but can cause mild vomiting, according to ASPCA Animal Poison Control).
 
Norfolk Island pines and rosemary plants are often sold as potted miniature holiday trees. These two plants aren’t toxic to cats and dogs. However, a miniature tree made of mixed greenery would be a serious danger if it contained yew.
 
Cyclamen (Cyclamen species)
Ingestion of cyclamen, a flowering houseplant, can cause drooling, vomiting, and diarrhea. Swallowing a large amount of cyclamen tubers can lead to heart rhythm abnormalities, seizures, and death.
 
Delphinium, larkspur (Delphinium species)
Blue delphinium flowers are included in some Hanukkah floral arrangements. Toxic compounds in delphinium block a neurotransmitter that’s required for muscle function. Ingestion can cause digestive system problems (vomiting, diarrhea, or constipation), belly pain, drooling, weakness, abnormal heart rhythm, tremors, seizures, and paralysis. The most severe effects—heart or lung failure and death—are most likely to happen in grazing animals that ingest large amounts of the plant.
 
Holly, winterberry, Christmas holly, English holly (Ilex aquifolium)
Ingestion of English holly and similar plants in the genus Ilex can cause vomiting and diarrhea. The pointed leaves can injure the inside of the mouth, leading to drooling and other signs of mouth discomfort.
 
Lily (Lilium species, Hemerocallis species)
Lilies of various types are common in floral arrangements, including arrangements for winter holidays. Some lilies are so toxic to cats that they shouldn’t be brought at all into a house with cats. The most dangerous lilies are Lilium species (Easter lily, Japanese lily, Asiatic hybrid lilies, stargazer lily, Casablanca lily, and tiger lily) and Hemerocallis species (daylily). Ingestion of a tiny amount of plant material—even licking pollen from a paw—can cause kidney injury in cats. Calla lilies, peace lilies, lily of the valley, and Peruvian lilies are not Lilium and Hemerocallis species; these plants don’t damage the kidneys but can cause stomach upset and other problems.
 
Mistletoe (Phoradendron species, Viscum album)
Mistletoe ingestion can cause vomiting, diarrhea, and abdominal pain in animals. Swallowing large amounts can cause low heart rate, a drop in blood pressure, uncoordinated gait, and seizures. American mistletoe (Phoradendron species) is less toxic than European mistletoe (Viscum album).
 
Paperwhite (Narcissus papyraceus)
Paperwhites and other Narcissus species (like jonquils and daffodils) cause severe vomiting and diarrhea if ingested. Swallowing a large amount can lead to breathing and heart rhythm abnormalities. The most toxic part of the plant is the bulb.
 
Poinsettia (Euphorbia pulcherrima)
Poinsettias are not as toxic as some have been led to believe, according to ASPCA Animal Poison Control. The thick, milky sap is an irritant that can cause drooling and vomiting if ingested. The sap can also irritate the skin and eyes on contact.
 
Yew (Taxus species)
Plants in the genus Taxus are highly toxic to all animals, including dogs, cats, horses, and people. Yew branches and berries are sometimes used to make holiday wreaths and other decorations. Be very careful displaying and disposing of items that might contain yew; be sure pets and wildlife can’t access them. Yew ingestion causes vomiting, muscle tremors, difficulty breathing, heart failure, seizures, and death.
 
Sources

• ASPCA Animal Poison Control toxic and nontoxic plants list: https://www.aspca.org/pet-care/animal-poison-control/toxic-and-non-toxic-plants
• North Carolina Extension Gardener plant toolbox: https://plants.ces.ncsu.edu/
• Pet Poison Helpline poisons list: https://petpoisonhelp.wpengine.com/poisons/

 
Public domain photo of yew (Taxus baccata) by MM on Wikimedia Commons

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