Xylitol is used as a sugar substitute, and you can find it in many types of gum, candy, breath mints, toothpaste, mouthwashes, baked goods and other products.
Dog owners [and all people who love dogs] should be as cautious about xylitol as they are with antifreeze or rodent bait. This stuff can kill.
Harley's human, Stephanie Lam, told their story to Linda Goldston of the Mercury News:
"Right before Christmas, my pug, Harley, ingested a couple of small breath mints containing xylitol...Here'a a link to the ASPCA Poison Control Center's page on xylitol, and the obligatory Snopes link.
"It nearly killed Harley. Within hours, she went into acute liver distress. Her liver enzymes, which in a normal dog should be in the hundreds, were at 7,500. Her blood pressure was so low that my vet feared she would not be able to administer an IV catheter.
"Harley required two blood plasma transfusions and countless other medical treatments. I was extremely lucky that she even survived. The vet that saved her specialized in toxicology and said that xylitol-related deaths and poisonings are becoming more common. I talked to the dog owners in my group, and none of them knew xylitol was toxic to dogs - nor what types of products contained it."
Right now, xylitol is used mostly in cookies, candies, cupcakes and other sweets developed for people who have diabetes. It's also sold in bags of crystals for baking. Because of its bacteria-killing properties, it is put into some oral care products, including Tom's All Natural and Biotene toothpastes.
It also is beginning to be used in a broad assortment of products intended for the general public. Among them: Jello sugar-free puddings and a wide variety of sugar-free gums, including Trident, Orbit, Stride, Icebreakers and Altoids. [Source.]
Stephanie says that xylitol should be as familiar to dog people as antifreeze, and as carefully managed if not avoided altogether. I couldn't agree more. Over at Dolittler, Dr. Patty Khuly has written a number of posts about this sweetener: here's the most recent one. Check them out, and spread the word — xylitol can kill, and it's killing more dogs each year.
[On the right, happy Harley, alive and kicking, vivita y coleando. "I'm well!"]