Xylitol toxicity for dogs.

Worked example

A 20 lb (9.1 kg) dog eats 5 pieces of gum with 0.5 g of xylitol each: 2.5 g in total, and 2.5 / 9.07 = 0.28 g/kg. That is well over the 0.075 g/kg line used here for dangerous low blood sugar, so this is an emergency. For the same dog the line is 0.075 x 9.07 = 0.68 g, only about one and a third pieces of that gum.

How it works

Dose = xylitol eaten (g) / body weight (kg). In dogs xylitol triggers a rush of insulin that can cause low blood sugar at about 0.1 g/kg, and doses above about 0.5 g/kg are linked to liver failure (Merck Veterinary Manual; ASPCA). To be conservative this tool flags a dangerous dose from 0.075 g/kg, this tool's own conservative margin below Merck's 0.1 g/kg.

Products rarely print grams of xylitol, and amounts differ by brand and flavour, so the per-piece figure is the weak link: use the label, call the maker, or assume the higher end. Dogs, not people, are affected this way, and other animals can also be harmed. Signs include vomiting, weakness, wobbling and seizures, but treatment should start before they appear. Under the threshold is not safe: always call.

Sources and basis (checked 2026-10-05): Merck Veterinary Manual, Xylitol Toxicosis in Dogs; ASPCA Animal Poison Control; Pet Poison Helpline. The 0.075 g/kg line is this tool's own conservative margin below Merck's 0.1 g/kg.

FAQ

How much xylitol is toxic to dogs?

About 0.1 g per kg of body weight can cause dangerously low blood sugar, and more than about 0.5 g/kg is linked to liver failure. This tool flags from 0.075 g/kg to be conservative.

My dog ate sugar-free gum. What should I do?

Call a vet or poison line right away. Do not wait for signs, because blood sugar can drop within 30 minutes. Tell them the brand, how many pieces and your dog’s weight.

How much xylitol is in a piece of gum?

It varies, often about 0.2 to 1 g per piece, and not every maker prints it. Use the label if you can, otherwise ask the manufacturer.

Which products contain xylitol?

Sugar-free gum and mints, some peanut butters, sugar-free baked goods, some toothpaste, mouthwash, vitamins and gummies, and some medicines. Check the ingredient list for xylitol or birch sugar.

Is a small amount of xylitol safe for a dog?

No amount should be assumed safe. Small dogs reach a dangerous dose from very little, so always call a vet.