Ragwort / Tansy
Senecio jacobaea or Tanacetum vulgare
Yes. Keep it out of reach.
Ragwort (Senecio jacobaea) and Tansy Ragwort are highly toxic plants for cats due to pyrrolizidine alkaloids (PAs) — compounds that cause severe, often irreversible…
Symptoms reported in cats
Most serious first.
- 1 Liver damage Not specified in the provided sources. · Liver damage occurs due to the pyrrolizidine alkaloid content of Ragwort. The cat must ingest the plant in large quantities to suffer this damage. Fortunately, Ragwort is quite unpleasant to eat, which usually acts as a natural deterrent and stops most cats from consuming it.
Important notes
Ragwort (Senecio jacobaea) and Tansy Ragwort are highly toxic plants for cats due to pyrrolizidine alkaloids (PAs) — compounds that cause severe, often irreversible liver damage. The toxicity is cumulative; even small repeated exposures cause progressive hepatic necrosis that may not become apparent until liver failure is advanced.
- Toxic compounds: pyrrolizidine alkaloids (jacobine, senecioline, retrorsine); all parts toxic; hay containing ragwort retains toxicity when dried
- Mechanism: PAs are metabolised to reactive pyrroles in the liver, forming DNA cross-links and destroying hepatocytes; damage is cumulative and irreversible
- Symptoms: weight loss, lethargy, jaundice, neurological signs (head-pressing, blindness, circling); acute liver failure may occur with large single exposures
- Dried ragwort in hay is a particular risk — it loses bitterness but retains full toxicity
- Seek veterinary care promptly; early intervention before liver failure occurs greatly improves prognosis
This summary was compiled from multiple sources and is for informational use only. It is not a diagnosis or treatment plan. Toxicity varies with the substance, amount, plant part and the individual cat. If you think your cat may have been exposed to a toxic substance, contact a veterinarian right away.