Scotch Broom Poisoning in Cats

The primary toxin in the Scotch broom weed is quinolizidine alkaloids. Scotch broom poisoning in cats may not be severe. However, if your cat ingests large quantities of the Scotch broom, they may develop serious and possibly life-threatening symptoms. If you believe your cat has ingested the Scotch broom, take it to the vet immediately.

The Scotch broom is a type of flowering shrub is toxic to dogs and cats. It is technically classed as an invasive species and grows across the east and west coasts. Recognize the Scotch broom by its spade-shaped, yellow petals. 

Mild symptoms of Scotch broom poisoning typically appear quickly following ingestion, most commonly within forty-five minutes. Symptoms may manifest as much as four hours following ingestion, however. Take your cat to the vet immediately if you notice any of the following symptoms.

• Vomiting
• Abdominal pain
• Lethargy and weakness
• Loss of coordination*
• Increased heart rate*

*Denotes serious symptoms that usually appear when large quantities of the Scotch broom are ingested. 

Types

The Scotch broom is known by several different names, including:

• Cystisus scoparius
• Broomtops
• Common broom
• European broom
• English broom
• Irish broom

The cause of Scotch broom poisoning is ingestion of the flower. The main toxin in the Scotch broom is quinolizidine alkaloids, specifically cytisine. Cytisine acts like nicotine in the gastrointestinal tract and in the nervous system. Humans have often smoked plants within the Cytisus family because they have similar effects to nicotine and can be mild hallucinogens. 

When ingested by domestic animals such as dogs and cats, the Scotch broom can cause mild gastrointestinal upset and cardiac signs. Cats are not likely to ingest large quantities of the Scotch broom because the plant has a foul odor and taste. Vomiting usually occurs quickly after ingestion, which also prevents cats from eating large quantities. Even if symptoms appear to be mild gastrointestinal signs, you should consult your vet immediately if your cat has ingested the Scotch broom.

If your cat is experiencing severe cardiac and/or neurological signs, call your vet before you arrive to inform them of your cat’s condition. Always inform your vet of how long your cat has been exhibiting symptoms. If you’re able to provide an estimate of how much of the plant your cat ingested, this may be helpful, although not necessary, for making the diagnosis.

Blood and urine analysis, in addition to physical examination, are typically sufficient to confirm Scotch broom poisoning. Your vet may perform a neurological exam, a CT scan or an ECG if severe symptoms are present.

Mild cases of Scotch broom poisoning are treated using standard procedure for plant poisoning. This involves the administration of activated charcoal, intravenous fluid therapy, and the use of antiemetic drugs. Activated charcoal will absorb undigested quinolizidine alkaloids in your cat’s stomach. Intravenous fluid therapy can restore normal fluid levels in cats that won’t eat or are dehydrated. Antiemetics are used to control persistent vomiting. Other treatments or medications may be prescribed based on your cat’s symptoms. Dietary changes may also be recommended, particularly if your cat has a habit of eating plants. This may be an indication that your cat is not receiving adequate nutrition.

Severe cases of Scotch broom poisoning are usually treated on a symptomatic basis. Your vet may recommend hospitalization if your cat has experienced severe cardiac or neurological signs.

Prognosis for most mild cases of Scotch broom poisoning is usually good or excellent provided the poisoning is diagnosed and treated quickly. Cats usually recover from Scotch broom poisoning within 24 hours following treatment. Prognosis for severe cases of Scotch broom poisoning in which cardiac or neurological signs are present may be guarded.

Follow-up appointments are generally not required for mild cases of Scotch broom poisoning. If your cat has ingested large quantities of the Scotch broom and exhibited severe clinical signs, your vet may schedule follow-up appointments as needed to monitor cardiac and neurological function. During these appointments, your vet may take additional CT scans or ECGs to ensure the heart and brain are functioning normally.

Since the Scotch broom is a weed, your cat is likely to have encountered it during outdoor activity. If this is the case, it may be a good idea to reduce your cat’s outdoor activity to prevent future cases of poisoning. If you notice any Scotch broom growing in your own lawn or garden, removing them can help prevent future cases.