By Sharon L. Peters, Special for USA TODAY
Xylitol, popular in Europe for decades but a relative newcomer to the U.S. alternative-sweeteners market, can be "very, very serious" to dogs when ingested, says Dana Farbman, spokeswoman for the Animal Poison Control Center of the American Society for the Prevention of Cruelty to Animals.
"It doesn't take a whole lot (of xylitol), and the effects are so rapid that the window of opportunity to treat the dog is extremely small," Farbman says.
The ASPCA sent an advisory to veterinarians last August warning them about the potential for serious harm or death. Veterinarians have used a variety of means to get the word out, including posting signs in their offices and making copies of the bulletin for clients to augment the caution the ASPCA has posted on its website.
Concerned that millions of people are still unaware of the risk, veterinarians with forums for widespread public announcements are spreading the word that way as well. Among them: Miami veterinarian Patty Khuly wrote about the problem on her doolittler.com blog, and Colorado Springs veterinarian Anne Pierce devoted her entire weekly newspaper column a week ago to xylitol.
Within 30 minutes of consuming a small amount of a xylitol-sweetened product, the ASPCA says, dogs can experience a dramatic drop in blood sugar, and they usually begin vomiting, become lethargic and can have difficulty standing or walking. Some have seizures, develop internal hemorrhaging and lesions and suffer liver failure. As few as two or three sticks of xylitol gum could be toxic to a 20-pound dog, the ASPCA says.
Immediate and aggressive veterinary treatment, which includes glucose drips and IV fluids, has proved effective in many cases.
The ASPCA's poison control unit is aware of 10 dog deaths from xylitol since 2002, and it has received scores of reports of dogs becoming gravely ill. But only a fraction of veterinarians and consumers alert the ASPCA when a dog becomes ill or dies from toxins, and there is no national clearinghouse tracking xylitol-suspected toxic reactions.
Moreover, it's not always entirely clear what caused the problem when a dog arrives at a veterinarian's office with seizures or liver failure. "I suspect that there are more cases than we know about because they come in with liver failure, and the owner is not aware of what has been ingested," Pierce says.
She believes that xylitol ingestion is "an emerging problem" and that the number of cases probably will increase with time, "depending on how widespread xylitol as a sweetener becomes."
Xylitol is an all-natural sugar substitute derived from beets, birch tree bark, corncobs and other natural sources. It's as sweet as sugar but has 40% fewer calories. Unlike sugar, xylitol does not require insulin to be metabolized.
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.
Makers of products with xylitol say their products are designed for people, including diabetes patients, who are seeking an alternative to sugar; they were never recommended for dogs and were never intended to be ingested by dogs. Owners should be careful because some dogs, Khuly says, "get into just about everything and eat everything they find."
There is no indication that any of the other sweeteners on the market adversely affect dogs. And there is no evidence so far that xylitol is toxic to pets other than dogs. But cats, for example, don't scavenge for sweets as dogs do, so it's possible there are risks that have not yet been discovered. For now, veterinarians advise pet owners to keep xylitol away from all animals.