Sugar substitutes have many benefits for people, including helping with weight loss, improving overall health, controlling diabetes, and reducing tooth decay. However, xylitol, an ingredient commonly used in sugar-free products, can be deadly for your pet. Our team at Billings Animal Family Hospital wants to help you protect your pet by offering information about this harmful toxin.

What pet owners should know about xylitol basics

Xylitol is a five carbon sugar alcohol that was first identified in 1891 by a German chemist named Emil Fisher. The substance is found naturally in berries, plums, corn, oats, mushrooms, lettuce, trees, and other fruits, but for commercial purposes, most xylitol is extracted from corn fiber or birch trees. Finland was the first to produce xylitol during World War II, when sucrose became unavailable. When the war ended and sucrose was available again, xylitol production was stopped, but commercial interest was revived in the mid-1970s. Efficient and economical techniques to produce xylitol, such as using corncobs left over from ethanol production, have continued to increase xylitol’s availability. Xylitol has many beneficial properties for humans.

  • Less calories — Xylitol is as sweet as sucrose, but has only two-thirds the calories.
  • Low glycemic index — Xylitol, which causes a negligible insulin release in people, is a good sugar substitute for people on a low carbohydrate diet, and those concerned with the food’s glycemic index.
  • Energy source for diabetics — Because xylitol doesn’t require insulin to enter cells, the substance can be used as an oral and intravenous energy source for diabetics.
  • Oral care products — Xylitol prevents oral bacteria from producing acids that damage tooth surfaces, and is a popular ingredient in sugar-free gum, toothpaste, and other oral care products.

What pet owners should know about xylitol metabolism

Xylitol is metabolized differently in different species. Humans, rats, rhesus monkeys, and horses metabolize xylitol in one way, while dogs, rabbits, baboons, cows, and goats metabolize the substance in another way. Little data is available for how xylitol is metabolized by cats and ferrets.

  • Humans — Once ingested, xylitol is absorbed slowly over three to four hours, and the increase in insulin levels after xylitol ingestion is negligible compared with the increase after glucose ingestion.
  • Dogs — Once ingested, xylitol is absorbed quickly, reaching peak plasma levels in about 30 minutes. This leads to a dose-dependent 2.5- to 7-fold increase in insulin levels compared with ingestion of an equal amount of glucose.

Small studies have been performed that indicate xylitol is not toxic to cats, but caution should be used until more is known. The safest recommendation is to avoid giving any pet xylitol.

What pet owners should know about xylitol toxicity

Xylitol is extremely dangerous for dogs, and small amounts can lead to deadly consequences. These effects include:

  • Hypoglycemia — The dog’s pancreas confuses xylitol with real sugar, and releases insulin to help store the “sugar.” In addition, the pancreas has an exaggerated response, releasing much more insulin than needed for a similar amount of glucose. Profound hypoglycemia results, causing signs including vomiting, disorientation, weakness, incoordination, tremors, and potentially seizures. Signs typically manifest about 30 minutes after xylitol ingestion.
  • Liver damage — At higher doses, xylitol can cause liver damage. The exact mechanism is unknown, but surprisingly, not all dogs who experience liver damage have hypoglycemia. Acute liver failure typically results in internal hemorrhage and clotting inability. The prognosis for dogs who develop liver failure after xylitol ingestion is guarded to poor.

What pet owners should know about xylitol toxicity treatment

Knowing the exact amount of xylitol your dog ingested is helpful to determine their treatment, and the sooner their treatment begins, the better their prognosis. The typical first step is inducing your dog to vomit, to remove the xylitol from their stomach. They then will usually be started on an intravenous dextrose drip for about 24 hours, and their liver enzymes and blood clotting factors monitored for two to three days. Blood transfusions may be necessary if clotting abnormalities occur.

What pet owners should know about preventing xylitol toxicity

Steps you can take to safeguard your pet and decrease their xylitol ingestion risk include:

  • Reading the ingredients — Before offering your pet any human food, such as peanut butter, read the label to look for xylitol. Also, avoid products labeled with words such as “reduced sugar,” “diabetic friendly,” “sugar-free,” and “cavity preventing.”
  • Keeping products out of reach — Keep all gum, candies, and mints, which could contain xylitol, out of your pet’s reach, and ensure your pet can’t access your guest’s purses or coat pockets that may hold the items.
  • Be prepared — Put Billings Animal Family Hospital and Animal Poison Control in your contact list, so you can easily reach help if your pet ingests xylitol. 

Xylitol toxicity is a concerning hazard, but you can take steps to protect your pet from this deadly toxin. Should your pet ingest xylitol, however, immediately contact our Billings Animal Family Hospital team, so we can provide the care they need.