Xylitol-based water additives: safe for pets

WCVM assistant professor Dr. Canadace Grier-Lowe examines the teeth of her dog Lola. Photo: Debra Marshall.

Xylitol, a natural sugar substitute, is added to some oral hygiene products for humans including chewing gum, toothpaste and mouthwash. With 40 per cent less calories than regular sugar, xylitol is also commonly found in human diet and baking products – advertised as safe for diabetics and other individuals with high blood glucose levels.

Although it has no known toxicity in humans, xylitol can be potentially toxic to pets. What’s most concerning is when pets eat cakes, biscuits, cookies or other baked goods that contain xylitol as a low-calorie sweetener.

However, xylitol has another potential benefit that was the focus of a recent study by Dr. Candace Grier-Lowe, an assistant professor at the Western College of Veterinary Medicine. The researcher investigated the effectiveness of a water additive called Breathalyser^® for reducing plaque and calculus in pets.

The product’s key ingredient is xylitol – a natural sugar often found in human oral hygiene products. Xylitol reduces cavities in people by killing the common cavity-causing bacteria, Streptococcus mutans. But since the water additive has such a low concentration of xylitol, Grier-Lowe says toxicity isn’t a concern.

“I feel safe giving it to my little dog. There’s not enough xylitol in it to cause any harm,” she says, adding that the product recommends a maximum daily dose of 50 milligrams.

According to Grier-Lowe, a dose of less than 100 milligrams per kilogram (mg/kg) of body weight rarely causes problems, but larger amounts are a different story.

“Dogs ingesting more than 100 mg/kg often present with a significant and rapid on-set of hypoglycemia or low blood sugar due to excessive insulin release,” explains Grier-Lowe.

However, she points out that symptoms vary with individuals. Some dogs will have a huge response to a very small dose of xylitol, while others will have little to no response with a large dose.

Here are some important facts that Grier-Lowe says all pet owners should know when it comes to xylitol:

• a stick of xylitol-containing chewing gum contains 1,000 mg of xylitol – enough to potentially kill a 10-kilogram dog.
• aside from hypoglycemia, other symptoms of overdose include lethargy, loss of co-ordination, collapse and seizures.
• a dose of greater than 500 mg/kg can cause severe liver damage and blood clotting deficiencies.
• treatment commonly involves hospitalization with intravenous (IV) fluid therapy and regular monitoring of blood glucose levels, liver function and clotting parameters.
• severe hypoglycemia requires the addition of dextrose – a sugar structurally similar to glucose – to IV fluids.
• chances of recovery are good if a diagnosis is reached quickly and treatment is started immediately.