PupkeeperToxicEmergency
Is water hemlock toxic to dogs?
Extremely toxic. Water hemlock, one of North America's most toxic plants, causes rapid seizures and breathing failure, even in small amounts.
If your dog ate or touched this, call your vet or a pet poison line now
United States
Poison lines in other countries: United Kingdom, Australia, Canada, New Zealand
What to do now
- Call your vet or a pet poison line now.
- Head to an emergency vet right away, even if your dog seems fine.
- Bring a piece of the plant in a bag, or a photo, to help identify it.
Don't
- Don't make your dog vomit unless a vet tells you to.
- Don't give milk, oil, salt or other home remedies unless a vet tells you to.
Signs to watch for
- Severe stomach pain
- Diarrhea
- Tremors
- Seizures
- Dilated pupils
- Fever
- Slowed breathing
- Abnormal heart rhythm
When signs appear: Rapid
Why
It contains cicutoxin, a poison that causes seizures. The roots hold the most toxin.
Sources
- ASPCA Animal Poison Control: Water Hemlock
- Pet Poison Helpline: Water Hemlock
- Pet Poison Helpline: Toxic Plants to Pets (first aid)
Guide reviewed 9 October 2026.
General information from the sources above, not a diagnosis. When in doubt, call your vet.