Xylitol is safe for humans. In dogs, it triggers a life-threatening insulin response and can cause acute liver failure — sometimes from a single piece of gum. Here's everything you need to know.
What Is Xylitol?
Xylitol is a sugar alcohol used as a sugar substitute in hundreds of consumer products. It's valued for being low-glycemic, tooth-friendly, and naturally derived (typically from birch trees or corn cobs). For humans, it's safe and beneficial. For dogs, it's a potentially fatal toxin.
Why Xylitol Is Dangerous for Dogs
In humans, xylitol does not significantly stimulate insulin secretion. In dogs, the pancreas mistakes xylitol for sugar and releases a massive surge of insulin — far more than the blood sugar level warrants. This causes severe hypoglycemia (low blood sugar) that can develop within 30–60 minutes of ingestion.
At higher doses, xylitol also causes acute hepatic necrosis — liver cell death — through a mechanism not yet fully understood. Liver failure can occur without the hypoglycemia phase, and may not manifest until 24–72 hours post-ingestion, making it particularly dangerous because the dog may appear to recover before collapsing.
How Much Is Toxic?
The toxic dose for hypoglycemia is approximately 0.1g/kg of body weight. The toxic dose for liver failure is approximately 0.5g/kg. To put this in context:
| Dog Weight | Hypoglycemia Threshold | Liver Failure Threshold |
|---|---|---|
| 10 lbs (4.5kg) | 0.45g xylitol | 2.25g xylitol |
| 25 lbs (11kg) | 1.1g xylitol | 5.5g xylitol |
| 50 lbs (22kg) | 2.2g xylitol | 11g xylitol |
A single piece of sugar-free gum typically contains 0.2–1.0g of xylitol. A small dog eating two pieces of sugar-free gum may have consumed a hypoglycemia-triggering dose. A larger dog eating several pieces could be at risk for liver failure.
Products That Commonly Contain Xylitol
This list is not exhaustive — always check labels. Products containing xylitol as an ingredient include:
- Sugar-free gum — especially Trident, Orbit, Ice Breakers, Stride, Pur Gum. Some regular gum also contains it.
- Sugar-free candies and mints
- Peanut butter and nut butters — some brands use xylitol. Always check before giving peanut butter to dogs. Brands currently known to use xylitol include Go Nuts, Nuts 'N More, and P28.
- Toothpaste and mouthwash — virtually all human dental products contain xylitol (another reason never to use human toothpaste on dogs)
- Chewable vitamins and supplements
- Cough syrup and liquid medications
- Baked goods made with xylitol
- Some yogurts — particularly low-fat and sugar-free varieties
- Protein bars and "keto" products
- Nasal sprays
Symptoms of Xylitol Toxicity
Hypoglycemia phase (30 minutes – 12 hours)
- Vomiting
- Weakness, lethargy, stumbling
- Loss of coordination
- Tremors or seizures
- Collapse
Liver failure phase (24–72 hours after ingestion)
- Jaundice (yellowing of skin, gums, whites of eyes)
- Vomiting
- Black or tarry stools (gastrointestinal bleeding)
- Coagulopathy (inability to clot blood — prolonged bleeding from minor cuts)
- Coma
What to Do If Your Dog Ingests Xylitol
Do not wait for symptoms to appear. Call immediately. Xylitol toxicity is a time-sensitive emergency — treatment is far more effective before symptoms develop.
- Call your vet or an emergency animal hospital immediately. Have the product packaging ready if possible — they'll want to know the xylitol content.
- Call ASPCA Animal Poison Control: (888) 426-4435 (consultation fee applies) or Pet Poison Helpline: (855) 764-7661
- Do not induce vomiting unless instructed by a vet. In some toxicity cases, inducing vomiting is appropriate; in others it isn't. Get professional guidance first.
- Do not wait to see if the dog "seems fine." Liver failure may not be apparent for 24–72 hours. If xylitol ingestion is confirmed, the dog needs veterinary evaluation even if asymptomatic.
Treatment
If caught early, a vet may induce vomiting to prevent further absorption. Treatment for hypoglycemia involves intravenous dextrose (glucose) administration and monitoring. Treatment for liver involvement includes supportive care, IV fluids, liver-protective medications, and monitoring of clotting function. With prompt, aggressive treatment, many dogs recover — but the prognosis worsens significantly with delayed presentation.
Prevention
- Check the ingredient list of all peanut butter and nut butters before giving to your dog
- Keep all sugar-free gum, candy, and mints out of reach — including in bags, purses, and car cup holders
- Never use human toothpaste on dogs
- Read labels on any sugar-free or "keto" food product before sharing with your dog
- Inform houseguests, especially those who chew sugar-free gum, about the hazard