White Snakeroot

Additional Common Names: fall poison, richweed, tremetol
Scientific Name: Eupatorium rugosum
Family: Asteraceae
Toxicity: Toxic to Horses
Toxic Principles: Trematol
Clinical Signs: Plant is toxic year round, although poisonings typically occur in summer and late fall. Horses eating one to ten percent of their body weight in the plant can develop lethal clinical effects. Onset of signs generally occurs after two days to three weeks of ingestion, and includes incoordination, muscle weakness and tremors, elevated heart rate, cardiac arrhythmias, profuse sweating, inability to swallow. The toxin is also passed in mare's milk; nursing foals can develop clinical signs as a result.

If your pet ingested this plant, contact your local veterinarian or the ASPCA Animal Poison Control Center at 888-426-4435.*

* A $65 consultation fee may apply.

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