Xylitol Poisoning in Dogs
If you’re a human, a sugar substitute may be beneficial. But if you’re a dog, it can be deadly. The substitute xylitol is potentially lethal.
Two Deadly Effects
In the canine body, the pancreas confuses xylitol with real sugar and releases insulin to store the sugar. The problem is that xylitol does not offer the extra calories of sugar and the rush of insulin only serves to remove the real sugar from the circulation. Blood sugar levels plummet resulting in weakness, disorientation, tremors, and potentially seizures.
It does not take many sticks of gum to poison a dog, especially a small dog (see below for toxic doses). Symptoms typically begin within 30 minutes and can last for more than 12 hours but, since xylitol can be absorbed into the body slowly, symptoms may not begin until 12 hours after the xylitol was eaten. Symptoms begin with vomiting and then progress to incoordination, collapse, and seizures.
The other reaction associated with xylitol in dogs is destruction of liver tissue. How this happens remains unknown but the doses of xylitol required to produce this effect are much higher than the hypoglycemic doses described above. Signs take longer to show up (typically 8-12 hours) and surprisingly not all dogs who experience hepatic necrosis will have had hypoglycemia first. A lucky dog experiences only temporary illness but alternatively, a complete and acute liver failure can result with death following. Internal hemorrhage and inability of blood to clot is commonly involved.
The hypoglycemic dose of xylitol for dogs is considered to be approximately 0.075 – 0.1 grams per kilogram of body weight (about 0.03 – 0.045 gram per pound). Chewing gum pieces have surprisingly variable amounts of xylitol depending on their flavor. (For example, most flavors of Orbit gum have about 0.009 grams of xylitol but their strawberry mint flavor has over 0.3 grams per piece). A small dog can easily be poisoned by a single stick of gum depending on the flavor, how much the dog ate, and the size of the dog.
Ideally, the patient can be seen quickly (within 30 minutes) and can be made to vomit the gum or candy. Beyond this, a sugar IV drip is prudent for a good 24 hours. Liver enzyme and blood clotting tests are monitored for two to three days. Blood levels of potassium are ideally monitored as well. Elevated blood phosphorus levels often bode poorly, and patients that develop hepatic necrosis usually do not survive.
What about Cats?
So far the ASPCA Animal Poison Control has no reports of xylitol toxicity in cats. At this time,toxicity in cats is unknown.
ASPCA Poison Control Line (888) 426-4435
Urban Animal Veterinary Hospital
1327 Yale St
Houston, TX 77008