canis - Articles
Xylitol toxicity
Synonym(s): Food additive E967 toxicity
Introduction
- A 5-carbon sugar alcohol.
- Used as an artificial sweetener in sugar-free chewing gums and confectionery, and as a sugar substitute in baking.
- An excipient in many human and some veterinary medicines.
- Used in some drinking water additives for animals to decrease dental plaque and calculus formation.
- Signs: xylitol is a potent stimulator of insulin release in dogs.
- Onset often within one hour; can be delayed.
- Hypoglycemia and/or hepatotoxicty.
- Hepatotoxicity may present as coagulopathy.
- Diagnosis: history, clinical signs.
- Treatment: supportive care.
- Hypoglycemia should be managed conventionally.
- Hepatoprotectant therapy may be used, although it has not been demonstrated to be beneficial in this toxicosis.
Presenting signs
- Hypoglycemia Hypoglycemia , initially characterized by vomiting, tachycardia, ataxia, drowsiness, coma, convulsions.
- Hepatopathy with coagulopathy. Hepatopathy may occur independently of hypoglycemia.
Acute presentation
- Vomiting.
- Hypoglycemia within 30-60 minutes if ingestion.
- Lethargy progressing to ataxia and collapse.
- Convulsions.
- Liver failure, which may occur in dogs that have not exhibited hypoglycemia.
- Liver failure may present as coagulopathy and/or icterus.
Geographic incidence
- The use of xylitol as an excipient and sweetener is increasing worldwide.
Breed/Species predisposition
Medical predisposition
- Dogs with pre-existing diabetes conditions are unlikely to be affected by xylitol ingestions.
Public health considerations
- None. Xylitol appears to be well tolerated in humans.
Cost considerations
- Costs of analyses.
Pathogenesis
Etiology
- Xylitol is a potent stimulator of insulin release in dogs.
- Whether administered orally or intravenously xylitol will cause dose-dependent increases in insulin concentrations in dogs.
Pathophysiology
- Doses in excess of 50 mg/kg may cause hypoglycemia.
- Hepatotoxicity is associated with doses in excess of 0.5 g/kg (500 mg/kg).
- Cases with fatal outcomes are reported at doses in excess of 1.4 g/kg; isolated fatal cases are reported at lower dosings.
- Dogs absorb xylitol more rapidly than humans.
- Xylitol is a potent stimulator of insulin release in dogs.
- Mechanism of hepatic damage remains unclear.
Timecourse
- Xylitol taken orally is absorbed very rapidly in the dog, with peak plasma concentrations occurring at about 30 min after ingestion.
- Onset of signs related to hypoglycemia may be present within 30-60 mins of ingestion.
- Hepatoxic effects usually occur 9-72 hours post ingestion, and may occur in dogs that have not shown signs of hypoglycemia.
Diagnosis
Subscribe To View
This article is available to subscribers.
Try a free trial today or contact us for more information.
Treatment
Subscribe To View
This article is available to subscribers.
Try a free trial today or contact us for more information.
Prevention
Subscribe To View
This article is available to subscribers.
Try a free trial today or contact us for more information.
Outcomes
Subscribe To View
This article is available to subscribers.
Try a free trial today or contact us for more information.
Further Reading
Publications
Refereed papers
- Recent references from PubMed and VetMedResource.
- Campbell A, Bates N (2010) Xylitol toxicity in dogs. Vet Rec 167 (3), 108 PubMed.
- Xia Z, He Y, Yu J (2009) Experimental acute toxicity xylitol in dogs. J Vet Pharmacol Therap 32 (5), 465-469 PubMed.
- Thomas H & Boag A (2008) What is your diagnosis? Hypoglycaemia. J Sm Anim Pract 49 (1), 47-49 PubMed.
- Todd J M, Powell L L (2007) Xylitol intoxication associated with fulminant hepatic failure in a dog. J Vet Emerg Crit Care 17 (3), 286-289 VetMedResource.
- Clarke D E (2006) Drinking water additive decreases plaque and calculus accumulation in cats. J Vet Dent 23 (2), 79-82 PubMed.
- Dunayer E K (2006) New findings on the effects of xylitol ingestion in dogs. Vet Med 101 (12), 791-797 ASPCApro.
- Dunayer E K, Gwaltney-Brant S M (2006) Acute hepatic failure and coagulopathy associated with xylitol ingestion in eight dogs. J Am Vet Med Assoc 229 (7), 1113-1117 PubMed.
- Cope R B (2004) A screening study of xylitol binding in vitro to activated charcoal. Vet Hum Toxicol 46 (6), 336-337 PubMed.
- Dunayer E K (2004) Hypoglycemia following canine ingestion of xylitol-containing gum. Vet Hum Toxicol 46 (2), 87-88 PubMed.
- Foss T S (2004) Xylitol: "Sweet" temptation for dogs. Vet Tech 25 (11), 773-775 ResearchGate.
- Asano T, Greenberg B Z, Wittmers R V et al (1977) Xylitol, a partial homologue of alpha-D-glucopyranose: potent stimulator of insulin release in dogs. Endocrinology 100 (2), 339-45 PubMed.
- Woods H A, Krebs H A (1973) Xylitol metabolism in the isolated perfused rat liver. Biochem J 134 (2), 437-443 PubMed.
- Kuzuya T, Kanazawa Y, Hayashi M et al (1971) Species difference in plasma insulin responses to intravenous xylitol in man and several mammals. Endocrino Japan 18 (4), 309-320 PubMed.
- Kuzuya T, Kanazawa Y, Kosaka K (1969) Stimulation of insulin secretion by xylitol in dogs. Endocrinology 84 (2), 200-207 PubMed.
- Kuzuya T, Kanazawa Y (1969) Studies on the mechanism of xylitol-induced insulin secretion in dogs. Effect of its infusion into the pancreatic artery, and the inhibition by epinephrine and diazoxide of xylitol-induced hyperinsulinaemia. Diabetologia 5 (4), 248-257 PubMed.
- Hirata Y, Fujisawa M, Sato H et al (1966) Blood glucose and plasma insulin responses to xylitol administrated intravenously in dogs. Biochem Biophys Res Commun 24 (3), 471-475 PubMed.
Other sources of information
- Dunayer E K (2008) Personal communication.
- Thrall M A, Baker D C, Campbell T W, DeNicola D, Fettman M J, Lassen E D, Rebar A, Weiser G (2004)Veterinary Hematology and Clinical Chemistry.Philadelphia, Lippincott Williams & Wilkins.
Organisation(s)
- ASPCA Animal Poison Control Center: www.aspca.org/pet-care/animal-poison-control, telephone (888) 426-4435.
- Veterinary Poisons Information Service (VPIS); www.vpisglobal.com, telephone + 44 (0) 2073 055 055.