English Yew Poisoning in Cats

English yew poisoning can be life-threatening and may cause sudden death if left untreated. If you suspect your cat has ingested English yew, take it to the vet immediately.  In order to secure the best possible prognosis, your vet will need to induce vomiting within an hour following poisoning. Unfortunately, many cases of yew poisoning are diagnosed post-mortem.

The English yew is a type of evergreen plant which is considered one of the most poisonous plants in North America. Any type of yew plant, including Japanese, Canadian, and Pacific yew, is toxic to many species of animals, including cats. The plant contains taxines A and B, which are highly toxic to cats. These substances primarily affect heart function. Higher concentrations of taxines in yew plants are prevalent during the winter months.

Symptoms of yew poisoning will manifest rapidly. You must seek treatment immediately if your cat has ingested yew. Be aware of the following symptoms:

• Drooling
• Vomiting
• Lethargy and weakness
• Tremors
• Difficulty breathing
• Seizures
• Dilated pupils
• Collapse or coma
• Unusual aggressive behavior

The primary cause of English Yew poisoning in cats is ingestion. Every part of the plant, including the leaves, seeds, and stems, contain poisonous taxines. The only part of the plant which isn’t toxic is the aril, which is the seed covering. Because volatile oil produces an unpleasant taste, it is unlikely your cat will consume large quantities of the plant. However, your cat only needs to ingest a very small amount of the plant to become poisoned and exhibit serious symptoms. Poisoning can occur even if your cat just chews on the leaves. There have been reported cases of horses collapsing within fifteen minutes of ingesting yew, so prompt treatment is vital for a good prognosis.

You should call the vet before you arrive to inform them that they will need to treat an emergency cause of English yew poisoning. If the plant is a house plant, take it with you when you go to the vet. Knowing approximately how much of the plant they ingested may be helpful for your vet when making the diagnosis, although this is not necessary.

You will need to tell your vet how long your cat has been experiencing symptoms. Your vet will confirm yew poisoning with standard diagnostic testing, including blood and urine tests. Your vet may also conduct a stomach acid test to confirm the presence of yew leaves or toxic taxines. Other tests may be used based on which symptoms are present or if any organ damage is suspected.

Treatment may vary depending on the severity of poisoning and the symptoms present. Depending on how severe the poisoning is, your cat may be hospitalized during treatment. 

There is currently no antidote for yew poisoning. Your vet will induce vomiting immediately to help purge the poison from your cat’s system. However, inducing vomiting may not be possible in cats that have ingested large quantities of the plant as this may result in complications in the heart and nervous system. Your vet may choose to pump your cat’s stomach instead. Intravenous fluid and nutritional therapy may be required in cats exhibiting fluid imbalances. Your vet may also administer activated charcoal in order to clear the toxin from your cat’s bloodstream. Medications that prevent seizures or help protect the gastrointestinal tract may also be prescribed. Other treatment methods may be utilized based on the specific symptoms present. Your vet may also recommend dietary changes, since plant consumption can be an indication that your cat is not receiving adequate nutrition.

Recovery and prognosis may vary depending on the severity of poisoning and how quickly it was treated. If your vet has recommended dietary changes, ensure you follow dietary guidelines to ensure your cat is receiving adequate nutrition.

If your cat came into contact with English Yew as a result of outdoor activity, you may want to limit your cat’s outdoor activity to prevent future poisoning. If your cat ingested English yew because you bought it as a house plant, you should dispose of it immediately. Before making any plant purchases,  research the plant you hope to purchase to ensure it’s not toxic to cats.

For some cases of mild poisoning that are treated quickly and successfully, follow-up appointments may not be required. For cats that have been seriously poisoned or sustained organ damage, your vet may schedule follow-up appointments as needed to monitor healing. During these appointments, your vet will monitor heart function closely.