Is American Mistletoe safe for cats and dogs?
| Species | Verdict |
|---|---|
| Cats | Toxic |
| Dogs | Toxic |
Severity: Moderate
Read the full first-aid guide: what to do if your pet ate something toxic
Mistletoe sprigs, often sold pre-bundled in small net pouches with a red ribbon, are a classic US Christmas doorway decoration hung overhead from Thanksgiving through New Year's at grocery stores, florists, and garden centers. American mistletoe (Phoradendron) is also a native parasitic plant that grows wild in host trees across much of the southern and eastern US, so a household can encounter it either as a purchased decoration or as a wild clump on a backyard tree.
Because it is typically hung out of reach, the most common exposure for cats is pulling down a low-hung sprig or chewing berries that have dropped after a dried-out bunch sheds; dogs more often find and eat a fallen sprig or bundle off the floor once it's within reach. Yard exposure is possible too if a mistletoe clump falls from a host tree after storms or pruning.
ASPCA lists American Mistletoe (Phoradendron flavescens) as toxic to dogs, cats, and horses, with toxalbumin and pharatoxin viscumin as the toxic principles. ASPCA and Pet Poison Helpline agree the typical reaction is gastrointestinal — vomiting, diarrhea, drooling — with low blood pressure and a slowed heart rate possible but rare, occurring mainly with large ingestions; VCA Animal Hospitals separately notes that more severe outcomes (collapse, ataxia, seizures, and death) have also been reported in large-ingestion cases. So mistletoe is genuinely toxic and not merely holiday folklore, but the popular image of it as an instant, severe cardiac poison overstates what a typical nibble causes. Because a serious outcome, while uncommon, is real, any owner who sees a cat or dog chew on mistletoe should call ASPCA Animal Poison Control (888-426-4435) or Pet Poison Helpline (855-764-7661) rather than wait to see if symptoms appear.
Facts and examples
- ASPCA lists American Mistletoe (Phoradendron flavescens) as toxic to dogs, cats, and horses, with toxalbumin and pharatoxin viscumin as the toxic principles. (source, verified 2026-07-28)
- ASPCA's documented clinical signs for American mistletoe are vomiting, diarrhea, low blood pressure (rare), difficulty breathing, and low heart rate. (source, verified 2026-07-28)
- Pet Poison Helpline states ingestion commonly causes gastrointestinal distress (vomiting, diarrhea), with low blood pressure and a stumbling gait possible only with large ingestions. (source, verified 2026-07-28)
- VCA Animal Hospitals reports that large ingestions of mistletoe have been associated with collapse, hypotension, ataxia, seizures, and death, in addition to milder GI signs. (source, verified 2026-07-28)
Verdict re-verified against aspca.org, 2026-07-28 — confirmed unchanged. Source
This page is for general information only and is not veterinary advice, diagnosis, or treatment. If your pet is showing symptoms, or you think they ate or touched something dangerous, contact your veterinarian or a pet poison-control hotline immediately.
Last verified 2026-07-28