Xylitol is an artificial sweetener used in many products including gum, mints, candy and even baked goods. When dogs ingest this compound, it causes insulin release from the islet cells of the pancreas. The insulin causes a drop in blood sugar. The drop is dose dependent which means the bigger the dose the more severe the drop in blood sugar. Dogs who ingest toxic doses of xylitol may be depressed, shaky on their feet, tremor and even seizure if blood sugar drops low enough. This effect lasts about twelve hours.
In addition to causing excessive insulin release, xylitol also harms the liver by causing necrosis. In my experience, the liver enzymes begin to rise about 12 hours after ingestion and peak about two days later. The full extent of liver damage may not be known for several days. Unfortunately, there are no antidotes for this poison in dogs. Victims of xylitol toxicity are treated symptomatically.
The key to treating this disease is to know how much xylitol was ingested. Doses of 1.6 to 2.0 mg/kg causes hepatic necrosis while doses of 0.2 to 0.4 mg/kg cause insulin release. Unfortunately, finding out how much xylitol is contained in a product can be difficult because manufacturers consider this information proprietary.
If you pet has ingested xylitol, seek medical help immediately. A great resource is Animal Poison Control Center. For $65.00 US, this 24 hours service will calculate the exact dose of poison ingested and provide guidance on further care. Their number is (888) 426-4435.
Sources:
-DeGioia, Phyllis. Once mum, gum maker to disclose xylitol content, VIN News Service, 4/16/2013.
-Shell, Linda Zylitol Toxicosis, VIN Canine Associate, 2/2/2006.