Xylitol is a sweetener that is becoming more widely used in a variety of foods. It’s tasty and low-calorie – and can have serious unintended health consequences, not for you, but for your pet.

In its pure form xylitol (“ZY-li-tol”) is a white crystalline powder, derived from various plants. It’s being touted as a safe sugar substitute for diabetics, and marketed as a low-calorie sweetener that decreases cavities. It is commonly found in gum, mints, hard candies and toothpaste. It can also be purchased in powdered form for cooking and baking.

While xylitol appears safe in people, its safety varies wildly in other species. Xylitol has shown no adverse effects in humans, rhesus monkeys, rats and horses but is toxic in dogs, baboons, cows and goats. There does not appear to be enough information about cats to decide whether it is toxic to them or not. I certainly would not take the chance.

Hundreds of cases of xylitol toxicity in dogs have been reported to the Animal Poison Control Center. Xylitol toxicity is dose-dependent – meaning the signs will vary depending on the weight of the dog and how much they ate. In dogs, xylitol ingestion causes a massive release of insulin. When insulin is released, blood sugar is lowered – and a sudden, large drop in blood sugar can cause weakness, staggering, seizures or death. Larger amounts can destroy liver tissue. Patients have tremendously abnormal liver tests and many will begin to hemorrhage and die.

So how much is too much? Surprisingly little. One to two pieces of xylitol-containing gum can cause hypoglycemia (low blood sugar) in a 20-pound dog. Eight to 12 pieces of gum can cause liver failure. Obviously, smaller dogs experience symptoms from even less, and larger dogs more. One published report concerned a dog fatality from eating four cupcakes with xylitol frosting. Another report cites a dog who died after eating one pudding cup with xylitol.

We all, as pet owners, need to start reading labels carefully. I was horrified to find xylitol gum in my daughter’s backpack – a place my golden retriever often investigates, looking for bits of leftover lunch. The pudding cup mentioned before said, “Sweetened with Splenda,” but xylitol was the second ingredient. It is finding its way into all sorts of products and foods. Check the labels before you bring these products into your home. If you use products with xylitol, make sure to store them safely. Most poisoning cases have been through accidental ingestion of gums or mints.

If you suspect that your pet has ingested xylitol, call your veterinarian or an animal emergency clinic immediately. We have products that are very effective at inducing vomiting, if we act quickly. If it has been more than a few hours, you should still call – some symptoms may not materialize for hours or days, and the animals may appear fine initially, but they are not. Prompt treatment is the only hope to save these pets, and in some cases, still may not.

The bottom line: Become educated. Read labels. Learn what products have xylitol and decide if you want them in your home. And always seek emergency care quickly if you think your pet has ingested any of these products. Untreated, even a few pieces of gum could be life threatening.