Dogs
Potentially toxicConsulted references classify the plant as toxic or irritating for that pet type.
Verified against ASPCA/provenance audit 2026-05-06 on May 6, 2026.
dog safety reference
Is Poison Hemlock safe for dogs?
Conium maculatum
Poison Hemlock is a highly dangerous biennial herb containing potent piperidine alkaloids that affect the nervous system. It is considered one of the most toxic plants and should be strictly avoided in any environment accessible to pets.
Conium maculatumDeadly HemlockPoison Hemlock
- Light
- Full sun to partial shade
- Habit
- Herbaceous biennial
- Care
- High (invasive weed)
Safety status
What this means for your dog
Poison hemlock is rated high severity for dogs by the NC State Extension Plant Toolbox — the whole plant is toxic and can be fatal. Dogs may chew the foul-smelling leaves or roots while exploring, and the alkaloids inside can shut down breathing. Treat any suspected ingestion as a 911-style emergency.
What to watch for
Per the NC State listing: salivation, vomiting, diarrhea, muscular weakness, trembling, dilation of the pupils, nervousness, weak pulse, paralysis, convulsions, and coma. Earlier signs (drooling, vomiting, wobbliness) usually appear before the more severe neuromuscular signs.
Time window
The NC State page does not give precise onset or recovery times. Clinical experience and toxicology references describe rapid onset (typically within 30 minutes to a few hours of ingestion) with potentially fatal respiratory paralysis within hours if untreated.
When to call the vet
Call immediately. Any amount of poison hemlock in a dog is a veterinary emergency — head to the nearest emergency clinic and call ASPCA Animal Poison Control at (888) 426-4435 on the way. Don’t wait for severe signs; the alkaloids can progress to respiratory failure quickly.
Sources: NC State Extension (no first-aid guidance).
If a pet has chewed or swallowed plant material and is showing symptoms, contact a veterinarian or poison resource immediately. This product is for structured reference, not diagnosis.
Dogs — concern notes
Common signs
Muscle weakness, incoordination, rapid heart rate, seizures, and respiratory failure.
Escalation note
The toxins in this plant act rapidly on the nervous system. Contact a veterinarian or animal poison control center immediately if your dog consumes any part of this plant.
Safer alternatives
No hand-picked alternatives for this plant yet. You can still pick your own using the Compare button on any other plant.
Source evidence
NC State Extension Plant Toolbox
botanical · 94% reliability
Conium maculatum is a highly poisonous plant that is toxic to humans and animals if ingested.
Same dog verdict
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