Xylitol Toxicosis in Dogs: An Update.

Xylitol ingestions in dogs may result in severe hypoglycemia followed by acute hepatic failure and associated coagulopathies. Aggressive treatment may be needed, but the prognosis is generally expected to be good for dogs developing uncomplicated hypoglycemia. Because of increased availability of xylitol-containing products in the market and in the dog's environment, it is likely that there will continue to be increased exposures and toxicity in dogs.

Xylitol toxicity in dogs.

Xylitol, a sugar substitute used in sugar-free gum, oral care products, and baked goods, is gaining popularity in the United States. Xylitol consumption is considered harmless to people but is known to cause life-threatening toxicoses in dogs. Dogs that ingest doses of >0.1 g/kg of xylitol are at risk for developing hypoglycemia, while dogs that ingest >0.5 g/kg may develop acute liver failure. Treatment includes dextrose supplementation for hypoglycemia and aggressive monitoring, treatment, and supportive care for dogs experiencing hepatotoxicosis. The prognosis for dogs with uncomplicated hypoglycemia is good, whereas the prognosis for dogs that develop severe hepatotoxicosis is guarded to poor.

Acute hepatic failure and coagulopathy associated with xylitol ingestion in eight dogs.

CASE DESCRIPTION: 8 adult dogs were evaluated for treatment of lethargy and vomiting after ingestion of xylitol, a sugar alcohol used as a sweetener in various products. CLINICAL FINDINGS: In addition to vomiting and lethargy, 5 of the dogs had widespread petechial, ecchymotic, or gastrointestinal tract hemorrhages. Common clinicopathologic findings included moderately to severely high serum activities of liver enzymes, hyperbilirubinemia, hypoglycemia, hyperphosphatemia, prolonged clotting times, and thrombocytopenia. Necropsies were performed on 3 dogs and severe hepatic necrosis was found in 2. In the third dog, histologic examination revealed severe hepatocyte loss or atrophy with lobular collapse. TREATMENT AND OUTCOME: Treatments varied among dogs and included IV administration of fluids; plasma transfusions; and, if indicated, administration of dextrose. Three dogs were euthanatized, 2 dogs died, 2 dogs made a complete recovery, and 1 dog was recovering but was lost to follow-up. CLINICAL RELEVANCE: Although xylitol causes hypoglycemia in dogs, hepatic failure after ingestion has not previously been reported. Because an increasing number of consumer products contain xylitol, clinicians should be aware that ingestion of xylitol can have serious, life-threatening effects.

Hypoglycemia following canine ingestion of xylitol-containing gum.

A 9-mo-old neutered male Labrador Retriever developed severe hypoglycemia, collapse, and seizures after consuming a large quantity of sugar-free gum sweetened with the sugar-alcohol xylitol. The dog was treated with i.v. boluses and continuous infusion of dextrose; its condition improved rapidly, but the dog remained mildly hypoglycemic for 11 hours before recovering fully. In humans, xylitol has little to no effect on plasma insulin or glucose levels, but in dogs xylitol is a strong promoter of insulin release and can cause severe hypoglycemia with ataxia, collapse and seizures. With the increased appearance of xylitol-sweetened products in the US, xylitol toxicosis in dogs may become more common.