Xylitol is a toxin that can cause hypoglycemia (low blood sugar) in cats. Xylitol is a sugar substitute commonly found in sugar-free gum, candy, baked goods, and other products. When ingested by cats, xylitol can cause a sudden release of insulin, leading to a rapid drop in blood sugar levels. This can cause a variety of symptoms in cats, including weakness, lethargy, vomiting, seizures, and even coma or death in severe cases. Other toxins that can cause hypoglycemia in cats include ethanol (found in alcoholic beverages), insulin (injected by humans with diabetes), and certain medications such as sulfonylurea drugs. It is important to keep these toxins away from cats and to seek immediate veterinary attention if a cat shows signs of hypoglycemia.