Cats
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.
Sources
cat safety reference
Is Poison Hemlock safe for cats?
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 cat
For cats, poison hemlock is a true emergency, not a stomach ache. ASPCA lists it as toxic to cats with neurotoxic alkaloids that can cause paralysis and death. Even a small chewed leaf or stem warrants an immediate call to a vet or animal poison control — do not wait to see how things develop.
What to watch for
Early: drooling, agitation or restlessness, dilated pupils, and tremors. Following: vomiting and diarrhea, weakness, ataxia (a wobbly, drunken gait). Severe: muscle paralysis, respiratory distress, collapse, and death. Cats hide illness, so any combination of trembling, drooling, and weakness after suspected exposure should be treated as serious.
Time window
ASPCA doesn’t list a specific window. The toxic alkaloids act on the nervous system rapidly; in published case reports, signs commonly appear within minutes to a couple of hours of ingestion and can progress to respiratory paralysis within hours.
When to call the vet
Call immediately. Any suspected ingestion of poison hemlock by a cat is an emergency — contact your nearest emergency veterinary clinic right away, and call ASPCA Animal Poison Control at (888) 426-4435 en route. Bring a piece of the plant if you can do so safely.
Sources: ASPCA (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.
Cats — concern notes
Common signs
Tremors, salivation, dilated pupils, respiratory distress, and potential paralysis.
Escalation note
This plant is extremely toxic; ingestion of even small amounts can be fatal. Seek immediate veterinary emergency care if ingestion is suspected.
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
ASPCA Toxic Plant List
toxicology · 99% reliability
Poison Hemlock is listed as toxic to both cats and dogs due to the presence of coniine and related alkaloids.
Same cat verdict
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