Fleabane poisoning can occur when your cat ingests or comes into close contact with the fleabane plant. These plants are found naturally throughout North America. The green, leafy plants produce pale purple flowers on long stems. The scientific name for fleabane is Erigeron speciosus and its common names include showy daisy, horseweed and seaside daisy. Young kittens are more prone to ingestion of the plant’s toxic compounds due to their curious natures and inclination to chew on plants. While fleabane poisoning is irritating and uncomfortable for your cat, poisoning is not generally fatal.

As with most cases of poisoning, the severity of symptoms in your cat will depend on the quantity of the plant ingested. Signs your cat may be suffering from fleabane poisoning include:

Fleabane is a plant that is found abundantly in the wild, typically in meadows or fields where it grows as a weed. The leaves and stems of fleabane tend to be woody and fibrous, making it difficult for your cat to ingest large quantities. The large, two-inch flowers grow on single stalks that extend from the base of the plant. The flowers are typically purple, pink, or white with clusters of long petals surrounding a yellow center.

Fleabane contains natural pesticides and fungicides that repel and kill small insects such as fleas, hence its name. Many people will grow fleabane in their garden to prevent fleas, which can increase exposure to neighborhood or wild cats. While their exact chemical properties are unknown, it is these same pesticides that are presumed to cause irritation and poisoning in your cat.

Diagnosis of fleabane poisoning will begin with a visit to your veterinarian’s office. If you suspect your cat is suffering from fleabane poisoning or plant poisoning of any kind you should attempt to bring a sample of the plant along for your vet to view. This will help your vet determine the most appropriate course of treatment and whether more aggressive measures will be needed. 

Your vet will thoroughly examine your cat’s mouth, face and paws for any signs of ulceration or irritation. Your vet may also want to collect blood and urine samples. Doing this will help rule out any alternative causes for the symptoms, some of which may be serious conditions. Even in cases of mild poisoning, this is also helpful for determining your cat’s overall health. In rare cases which extreme amounts of the plant have been ingested, a blood panel and full urinalysis will also confirm whether your cat’s liver, kidneys and other internal organs are functioning properly.

Since fleabane poisoning is considered mild and generally not  life-threatening, treatment will be supportive and will be aimed at helping manage your cat’s discomfort. Any plant material still present in your cat’s mouth should be immediately removed and your vet may flush your cat’s mouth with fluid in order to eliminate any residue.

While inducing vomiting is a typical treatment for poisoning, this will not generally be needed for fleabane poisoning since vomiting is a major symptom of the condition. It is often difficult to determine which exact plant or toxic compound your cat has ingested. In these cases, your vet may still wish to administer an emetic, or solution that causes your pet to vomit. The most common solution is a small amount of hydrogen peroxide mixed with water, typically given via a tube placed directly into your cat’s stomach through the mouth and dosed by body weight.

After your vet has eliminated as much of the plant from your cat’s system as possible, they may administer activated charcoal, which absorbs chemical toxins from your cat’s stomach and allows them to pass harmlessly through your cat’s digestive system without being further absorbed by the body.

In most cases, your cat will make a full recovery from fleabane poisoning. After treatment and removal of excess plant material from their system, your cat should begin to show improvement within a few hours, with complete recovery within 24 hours. In some cases, your cat may need IV fluids to counter any dehydration from vomiting or diarrhea. Your vet may recommend encouraging your cat to drink more water by providing a second water dish of diluted chicken broth for several days.

As a preventative measure, you should search your yard for any remaining fleabane plants and properly dispose of them, eliminating your cat’s ability to ingest the plant in the future.