Some Sweeteners Are No Good For Dogs: The District Vet

Beware of Xylitol

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Not all that is sweet is good for your dog. In our quest for lower glycemic index and reduced calorie sweeteners, xylitol has become a more prevalent alternative to sugar within various foods. To us, it tastes similar to white sugar, aka sucrose. And to dogs, unfortunately it tastes the same. While safe and harmless for human consumption, xylitol may be toxic to dogs, leading in some cases to death. 

Xylitol is a naturally occurring alcohol found in low concentrations in corn fiber, berries, plums, oats, mushrooms, birch trees and more. When refined, it resembles and tastes like sugar. its popularity has increased greatly, seeing that it has only 2/3 the calories of sucrose, is lower on the glycemic index (affects our blood sugar levels less than sugar), and reduces accumulation of dental tartar and plaque in people. You can find it in sugar-free chewing gums and mouthwashes, candy, pudding snacks, cough syrup, protein bars and powders, gummy chews, human medications, select peanut butters, baking powders, and more. New products containing xylitol emerge every year. In these products it is safe for humans, but in excessive quantities, it can act like a laxative. Frequently oral health products for dogs contain xylitol, but at such a small level that it is not dangerous when used as directed.

Many human medications contain toxic levels of xylitol. Take care when giving any over-the-counter medication (especially children’s syrups) to dogs. Some compounded medications made by human pharmacies may also contain dangerous amounts
of xylitol. 

In dogs though, xylitol can be deadly. Why? Remember that dogs are not small humans and their metabolic processes, although similar, contain important differences. Levels of sugar in the blood of dogs and humans is controlled by the hormone insulin, which is released by the pancreas. Xylitol does not cause a release of insulin in humans, but does in dogs—to an extreme degree. The rapid release of insulin may cause the circulating blood sugar level to drop to dangerously low levels quickly, within 10-60 minutes after eating the xylitol. Left untreated, this may result in death. Xylitol is also toxic to the liver in dogs. 

The amount of xylitol in products varies widely, with variations occurring between flavors of gum from the same manufacturer. Lower levels of xylitol may cause hypoglycemia (low blood sugar) whereas increased amounts may lead to irreversible liver damage. Manufacturers of products are not required to list the amount of ingredients in their wares, so determining how much xylitol has been ingested by a pet can be challenging. As little as 75 milligrams per kilogram can lead to hypoglycemia, and over 500 milligrams can lead to life-threatening acute liver failure. Eating powdered or readily-absorbed xylitol can have a fast onset of hypoglycemia. Gum may take a longer period of time to be digested, leading to a delayed onset of problems. 

Initial signs of toxicity may include a suite of non-specific problems: vomiting, diarrhea, lethargy, uncoordinated waking, restlessness, collapse, seizure, and coma. In liver failure, signs of vomiting, abdominal pain, and yellowing of the gums may develop within one to three days. 

If a dog eats a potentially toxic dose of xylitol, emergency measures should be taken. The first is removing the xylitol from the stomach via inducing vomiting. This is only done in an alert animal that is not in danger of accidentally aspirating (choking on and inhaling vomit). Their blood sugar levels are to be monitored carefully by the veterinarian until the risk of hypoglycemia has passed. In cases where large amounts have been ingested and there is a concern for liver failure, other medications, fluids, and supportive measures are taken. 

Prognosis for dogs with only hypoglycemia is good. With appropriate monitoring, fluids, and administration of IV dextrose (sugar), they usually make a full recovery. Those with liver damage have an uncertain and guarded prognosis at best. 

Dr. Teich is the medical director for District Veterinary Hospitals in Navy Yard, Eastern Market and Brookland.  Visit www.districtvet.com for more information.