Oh, by gosh by golly, it’s time for mistletoe and holly…. except when your pets are involved. Christmas is a time of not only holiday cheer but also holiday plants. If you bring these plants into your home, be wary of keeping them in your pet’s reach:
- Holly (Ilex): The holly plant contains saponins, which are irritating saps that occur within the plant material. While the berries of the holly are considered the most toxic, symptoms from ingestion are typically limited to gastrointestinal irritation (i.e. vomiting, diarrhea, and abdominal pain). Usually, pets experience mild signs and recover well at home. Some pets with more persistent or severe signs may require veterinary attention to help correct and prevent dehydration.
- American mistletoe (Phoradendron): All parts of American mistletoe are considered toxic. If a few leaves or berries are ingested, pets tend to experience mild gastrointestinal irritation. Larger ingestions pose a risk for more serious signs, including cardiovascular effects (changes in blood pressure and heart rate). Keep in mind many stores replace the real mistletoe berries with plastic ones. Ingestion of large amounts of these plastic berries can cause a foreign body obstruction.
- Amaryllis (Amaryllis): Also known as the Aztec lily, orchid lily, and naked lily. Thankfully, amaryllis is not considered a “true” lily. The toxicity of the amaryllis is due to an abundance of alkaloids present in all parts of the plant. Ingesting a few leaves can cause mild GI upset (vomiting) from the alkaloids. The alkaloids are the most concentrated in the bulb and ingesting a bulb or large amounts of leaves can cause low blood pressure, weakness, tremors, and seizures.
- Cyclamen: This popular plant contains irritating saponins that can cause vomiting and diarrhea. Ingestion of the leaves or flowers from a cyclamen can cause mild GI upset, though cats have been known to develop blood in the vomit and diarrhea. These saponins are at the strongest concentration in the roots of this plant. Ingesting the root or tuber can cause abnormal heart rhythms and convulsions.
- Christmas rose (Helleborus niger): Otherwise known as the Easter rose or black hellebore, the Christmas rose contains several toxic components. The saps within this plant can cause excessive drooling as well as persistent vomiting and diarrhea, often containing blood. The Christmas rose also contains cardiac glycosides which can cause electrolyte imbalances, changes in heart rate and rhythm, and hallucinations. The effects of cardiac glycosides can be fatal.
Less toxic Christmas plants include:
- Poinsettias (Euphorbia pulcherrima): The poinsettia plant contains a milky sap that can cause oral irritation and GI irritation. Most of the time, the irritation is mild and resolves on its own. Actual poisoning from a poinsettia is rare.
- Christmas cactus (Schlumbergera sp.): The Christmas cactus can cause GI irritation from leaf ingestion, leading to vomiting and diarrhea. Signs typically resolve within a few hours, though persistent irritation can require veterinary intervention.
- Christmas trees: The most common evergreens used as Christmas trees are Douglas fir (Pseudotsuga menziessii), Balsam fir (Abies balsamea), Fraser fir ( fraseri), pine trees (Pinus), and cypress trees (Cupress). Ingestion of these usually causes mild and self-limiting drooling and vomiting due to irritation. Irritation can be caused by tree sap, or by ingesting sharp needles or cones. While Christmas trees do contain essential oils, they are in low concentrations and are not expected to result in major toxicity.
Written by Persia Salehi, PPH DVM student extern, Iowa State University, Class of 2023
Lizzy Olmsted, CVT, Veterinary Information Specialist