Xylitol is a sugar substitute that is now widely used in the US. It is popular with dieters and diabetics alike because it is sugar free, has zero calories, and helps prevent tooth decay. It is commonly found in sugar-free gum, candy, and foods. In humans, xylitol is absorbed slowly and has little effect on blood sugar or insulin levels. But in the dog, xylitol is rapidly absorbed and causes a sudden spike in insulin, which in turn causes a sudden profound drop in blood sugar that can be fatal.
It takes surprisingly little xylitol to cause toxic signs in dogs. The ASPCA Animal Poison Control Center reports that a 10-pound dog could have toxic effects from as little as a stick and a half of gum! As the amount of xylitol ingested increases, the effects get worse and can be irreversible. Think about the damage a pack of gum could cause, or worse, an entire “cup” of gum! You are probably wondering right now where you left your gum and whether your dog could get into it! That is the problem. Unless pet owners are aware of the danger, it is all too easy for a “scavenger” dog to find and eat gum or sugar-free foods from a purse, car, backpack or grocery bag left on the floor.
The earliest sign of xylitol toxicity is vomiting, which then progresses to weakness, lack of coordination, collapse, and seizures. These signs can begin in as little as 30 minutes after ingestion or up to 12 hours later. At high xylitol doses in dogs, an even more serious and often irreversible reaction is destruction of liver tissue. This liver effect can take longer to show signs (8-12 hours) and surprisingly not all dogs who have liver damage show the earlier symptoms.
There is no antidote for xylitol toxicity. Because it can be so rapidly absorbed, it is imperative to seek treatment by a veterinarian immediately. Treatment may involve inducing vomiting, (depending on how long ago the xylitol was eaten), administering intravenous fluids containing dextrose (a form of sugar), and other supportive measures. Diagnosis is based on history of eating xylitol, typical symptoms, and blood test results showing low blood sugar, high liver enzymes, and other abnormalities. Because xylitol is so rapidly absorbed, there is no specific blood test for it and there is no benefit to administering activated charcoal. The outcome of xylitol toxicity is directly related to both the amount ingested and the time elapsed before seeking veterinary emergency care. The outcome can be good for those dogs who eat low doses and get rapid treatment. Dogs that ingest high doses, or dogs whose owners delay emergency veterinary care, can die.
The good news is that xylitol ingestion is preventable! Households with dogs should consider avoiding xylitol-containing foods. If they choose to have those foods at home, they must store them out of reach from the most curious canines. Recently, xylitol has even been found in some brands of peanut butter, which many dog owners use to hide pills or stuff Kongs. It is also in many toothpastes and mouthwashes, including dog products. Of course, dog dental products do not have toxic levels of xylitol if they are used correctly. But, if a dog accidentally finds and eats a whole tube of dog toothpaste, that could be potentially toxic.
In September 2021, the AVMA endorsed the federal Paws Off Act (HR 5261), which would require products containing the sugar substitute xylitol to include a warning label specifying its toxic effects to dogs. Let’s hope this bill passes and prevents countless xylitol poisonings and even deaths.
If your dog eats a xylitol-containing product, call the ASPCA Poison Control Hotline at (888) 426-4435.