Jerusalem Oak Poisoning in Cats

Mild cases of Jerusalem oak poisoning in cats are not usually life-threatening. However, Jerusalem oak poisoning can cause gastrointestinal upset for your cat, and serious poisoning can result in death. If you suspect your cat has ingested any part of the Jerusalem oak plant, take it to the vet right away to relieve its discomfort.

Jerusalem oak is another name for the ambrosia Mexicana plant. Jerusalem oak may also be referred to as feather geranium. While humans have used this plant as a medicinal remedy for centuries, the Jerusalem oak contains sesquiterpene lactones, which are toxic to cats. The Jerusalem oak grows in various locations and climes throughout North America and looks similar to a weed. Recognize the Jerusalem oak by its thin stems and small leaves.

Symptoms of Jerusalem oak poisoning usually manifest rapidly. If you notice any of the following symptoms, consult your vet right away:

• Vomiting
• Diarrhea
• Loss of appetite
• Drooling
• Signs of depression
• Hiding
• Excessive sleeping
• Pale tissue and mucous membranes*
• Tremors*
• Excessive urination*
• Lethargy and weakness*
• Loss of muscle control*

*Indicates severe and possibly life-threatening symptoms of nitrate poisoning. 

The primary cause of Jerusalem oak poisoning in cats is ingestion. Though sesquiterpene lactones are toxic to cats, these toxins may not be primarily responsible for poisoning. Environmental factors can influence the toxicity of the Jerusalem oak. Growing conditions determine the amount of excess nutrients, specifically nitrate, plants can hold or reserve. The Jerusalem oak’s stores of excess nitrate can cause severe poisoning in cats, in which symptoms may not manifest until several days following ingestion. This is usually associated with ingestion of larger quantities. Cats are unlikely to ingest large quantities of poisonous plants due to the rapid onset of symptoms. Nitrate poisoning most commonly affects livestock, however, nitrate poisoning can also affect cats if the specific Jerusalem oak plant ingested has grown in adverse environmental conditions.

If the Jerusalem oak is a house or garden plant, take a sample of it with you when you go the vet if you can. If you know approximately how much of the plant your cat ingested, provide this information to your vet. However, it is not necessary to make the diagnosis. Always tell your vet how long your cat has been experiencing symptoms.

Standard diagnostic tests such as complete blood count and blood and urine analysis can usually confirm plant poisoning. The blood of cats with severe nitrate poisoning will appear dark brown when drawn. Your vet may recommend other tests based on your cat’s symptoms.

Treatment will vary based on whether or not severe nitrate poisoning has occurred. Standard procedure for mild cases of poisoning is to induce vomiting immediately if possible. This will help clear the toxins from the cat’s gastrointestinal tract. In cats exhibiting fluid imbalances or dehydration, intravenous fluid therapy may be started right away. Activated charcoal may also be administered in order to absorb toxins from the stomach.

Cats with severe nitrate poisoning may be hospitalized and treated with sodium citrate via injection and/or oxygen therapy. These treatments will reduce the levels of methemoglobin in the blood. Inhibiting certain bacteria in the gut may also help convert poisonous nitrate into nitrite. Your vet may also administer vitamin supplements to restore normal vitamin and mineral levels in some cases.

Recovery and prognosis will vary based on the severity of poisoning and symptoms. Cats suffering from mild cases of poisoning usually recover within twenty-four hours. The prognosis for cats with nitrate poisoning is typically guarded.

If your cat encountered the Jerusalem oak while outdoors, it may be a good idea to limit your cat’s outdoor activity to prevent future poisoning, especially because the plant is so common. The Jerusalem oak is not commonly used as a decorative house or garden plant unless it is being used as a medicinal remedy. However, if you purchased the Jerusalem oak as a house plant, remove it from your home to prevent poisoning. Always research any plant you hope to purchase to ensure it does not contain substances that are toxic for your cat. Never assume your cat cannot reach a toxic plant because you place it in a hard-to-reach or secure area. Stay on the safe side and avoid purchasing toxic plants.

Follow-up appointments are not usually necessary for cats that have made a full recovery from a mild case of Jerusalem oak poisoning. Your vet may schedule follow-up appointments for cats with nitrate poisoning. During these appointments, your vet may take blood samples to ensure methemoglobin levels are back to normal.