Should your cat be one of the few that nibbles on this plant, it is at high risk of developing liver failure. Your vet needs to see it and run several tests to make sure of the cause of its symptoms so the most appropriate treatments can be given.

Golden ragwort, which comes from the Compositae family, is potentially deadly for cats who may eat the leaves and flowers. This plant doesn’t taste very good, so your cat may choose to stop eating it, but it will still need immediate veterinary care. Other names for this plant are cressleaf groundsel and butterweed. Younger plants are more toxic than older plants. Rather than being considered a houseplant, golden ragwort mainly grows outside, showing up in pastures. 

While this plant doesn’t taste good, there’s no predicting what your cat will be attracted to. Once it has eaten even a little golden ragwort, it will develop the following symptoms:

Symptoms of liver failure:

Signs of neurological problems resulting from liver failure:

These symptoms develop suddenly and progress rapidly, from a few days to a week. Golden ragwort is poisonous to your cat’s liver. If it manages to eat anything from this plant, your cat’s liver will not be able to continue processing toxins so they can be flushed out of its body.

The main toxins in golden ragwort are pyrrolizidine alkaloids. These are the poisons that lead to liver failure and, if your cat isn’t treated for its illness, death. The leaves, seeds, and flowers of this plant are all toxic to animals, including cats. 

If you allow your cat to roam outdoors, it may find a stand of golden ragwort and begin nibbling on it. It’s a hard plant to eradicate, preferring bare ground. If you find any growing, have a professional landscaper treat all areas with weed killers between late October and early November. These treatments are most effective before the plant begins to grow and flower in the spring. Once any areas of golden ragwort have been treated, you’ll have to keep your cat indoors and away from these treated areas so it won’t ingest those poisons.

Take your cat to the vet as soon as you realize it is sick. If you suspect the cat ate any golden ragwort, bring a small clipping in a plastic bag so the vet can test it while running diagnostic tests on your cat.

Your cat will undergo a physical, including blood work and urinalysis. If you have any fecal or vomit samples, bring these with you. Your vet may test these to narrow down the toxin making your cat sick. 

Over time, the effects of the toxins in golden ragwort are cumulative. Your vet will also take a small sample of your cat’s liver so it can be biopsied.

Treatment for your cat will be supportive and symptomatic. The vet will induce vomiting so your cat can get rid of any remaining golden ragwort in its stomach. Your cat will also be treated with activated charcoal, allowing the remaining toxins to bind to the charcoal so they can be safely eliminated from its body. The vet will treat its symptoms, providing an aggressive decontamination. This includes stomach pumping or gastric lavage.

Because symptoms appear unexpectedly, you won’t know what is causing your cat’s symptoms until the vet connects all the dots. This means symptoms of liver failure will develop as well. Unfortunately, if your cat’s illness wasn’t diagnosed in a timely manner, the damage to its liver will be permanent. Here, treatment will be supportive, as your cat will not regain its former level of health. Over time, its health will grow worse and the aim of treatment will be to ensure the cat is comfortable.

Your cat’s health will be permanently affected after being poisoned by golden ragwort. You’ll be able to bring it home, but you’ll only be able to provide supportive care and make it comfortable. 

Continue monitoring your cat’s health, noting symptoms related to liver failure. If you notice anything that indicates it is becoming worse, return to the vet for treatment. If the effects of poisoning are significant or its condition deteriorates, humane euthanization may be recommended.