Xylitol is a popular alternative sweetener to table sugar (sucrose) and is extremely toxic to dogs when ingested. Xylitol is advantageous to that of regular table sugar because it has the same level of sweetness and far fewer calories. Xylitol is used in a variety of food and non-food products, including sugar-free foods such as chewing gum, toothpaste, medications and others such as flavoured drinks and even peanut butter.
When ingested, xylitol is very toxic to dogs. Xylitol is rapidly absorbed following ingestion and will cause insulin release from the pancreas which causes the blood sugar (glucose) to drop to dangerously low levels. Even small doses will induce an exaggerated insulin release that is 5 times that caused by the equivalent amounts of dextrose and therefore results in hypoglycemia (low blood glucose levels).
Symptoms: Shortly after ingestion (30-60 minutes), dogs may show signs of lethargy, imbalance (ataxia), restlessness, anorexia (lack of appetite), vomiting, tremors and/or seizures. Signs of liver disease may also present 12-72 hours after ingestion and these could include jaundice, vomiting/diarrhea, anorexia and lethargy. This would represent hepatotoxicity from the toxin, i.e. xylitol.
Treatment: Because xylitol is absorbed quickly after ingestion, prompt treatment is required. Your veterinarian may recommend to induce vomiting if there is known exposure within 30-60 minutes. If your pet is showing signs of hypoglycemia as noted above, hospital care would be required by delivering dextrose (sugar) intravenously to help balance and counteract the high insulin levels. If there are no other signs of liver disease/hepatotoxicity, the prognosis is very good if treatment is implemented in a timely manner.
Prevention: It is very important to evaluate nutritional labels prior to giving your dog any human "treats". For example, xylitol can be found in some peanut butters and some owners routinely use this to help administer pills. Chewing gum is often very attractive to dogs and making sure this is not accessible to your dog is recommended. If you do find that your dog ingested something they shouldn't have, it is important to investigate the ingredient list of the ingested product and provide that information to your veterinarian.