Veterinary Q&A: Why is xylitol so dangerous for dogs and cats?Dr. Dana Brooks, an internist at Seattle Veterinary Specialists in Kirkland, answers this week's question.
Dr. Dana Brooks, an internist at Seattle Veterinary Specialists in Kirkland, reports an increased number of dogs and cats being treated at its emergency clinic -- in one case the dog died -- from eating xylitol, an artificial sweetener used as a sugar substitute in foods, including sugar-free gum, sugar-free mints, chewable vitamins, tooth paste and oral-care products. Xylitol is also available in a granulated form at your local grocery store for baking and beverage sweeteners.
Question: Why is xylitol so dangerous for dogs and cats?
Answer: Ingestion of xylitol primarily affects insulin release throughout the body. Insulin causes an increase of glucose (blood sugar) uptake into the liver, muscle, and fat cells resulting in decreasing blood glucose levels.
Xylitol strongly promotes the release of insulin from the pancreas into circulation leading to a rapid decrease of blood glucose levels. Hypoglycemia (low blood sugar) can occur within 30 to 60 minutes of xylitol ingestion with levels as low as 0.1g xylitol /kg body weight.
Hypoglycemia may compound further into liver toxicity, liver damage, and ultimately liver failure. Ingesting amounts of xylitol greater than 0.5 g xylitol /kg body weight increases the risk for developing liver toxicity.
Sugar-free chewing gum is the most common cause of dogs that present to the emergency room. However, the recent introduction of xylitol as a substitute for sugar in grocery stores has increased the potential for toxicity.
Xylitol is perfectly safe for people, but because of different metabolisms, it can be fatal for dogs and cats. A simple piece of cupcake or cookie could kill an animal if the danger is unknown and not addressed immediately.
Question: What are the signs my dog might have eaten xylitol?
Answer: Immediately after ingestion, vomiting may occur. Hypoglycemia (low blood sugar) develops within 30 to 60 minutes, resulting in lethargy and weakness. These signs may quickly develop into ataxia (trouble walking), collapse, and seizures. Prolonged blood clotting times as well as skin and intestinal hemorrhaging are clinical signs that may develop within hours and warrant a very poor prognosis.
Question: What do I do if I think my dog has eaten xylitol? What is the treatment and prognosis?
Answer: If xylitol ingestion occurs, consult your veterinarian immediately. Inducing vomiting to remove the xylitol is imperative, but close monitoring of blood sugar levels and intravenous infusions of glucose (sugar) may also be needed depending on the amount ingested and how quickly the problem was recognized.
The prognosis for dogs with hypoglycemia is good with immediate and proper treatment, while the prognosis for dogs that have developed liver toxicity is poor. Large ingestions of xylitol (a relatively small amount of the product) that are not caught immediately can result in fulminant liver failure and death despite aggressive supportive care. This can occur in less than 36 hours in dogs that are otherwise young and healthy.