Xylitol Toxicity
Xylitol is a sugar alcohol sweetener used in many sugar-free products — chewing gum, some peanut butters, baked goods, vitamins, and oral care products. In dogs, xylitol triggers a massive, life-threatening release of insulin causing severe hypoglycaemia (low blood sugar). At higher doses it also causes acute liver failure. Even small amounts can be fatal. It is not similarly toxic to cats.
Toxic mechanism: Causes massive insulin release → severe hypoglycaemia.
Understanding Xylitol Toxicity
Xylitol is present in surprisingly many household products beyond the obvious sugar-free gum. Check the ingredient list on peanut butter (especially brands marketed as 'healthy' or 'natural'), sugar-free baked goods, mouthwash, toothpaste, chewable vitamins, some medications, and even sugar-free nut butters. The dose required to cause hypoglycaemia in dogs is relatively low — approximately 0.1g/kg body weight — making a single piece of many brands of sugar-free gum potentially dangerous to a small dog.
Symptoms of xylitol toxicity appear rapidly — within 15–60 minutes of ingestion. Hypoglycaemia causes: vomiting, weakness, lack of coordination, tremors or seizures, and collapse. Liver failure, which develops at higher doses, may not manifest until 24–72 hours after ingestion with signs of jaundice, vomiting, and bleeding tendency. The rapid onset means there is very little margin for 'watching and waiting.'
If you suspect xylitol ingestion, call your vet or ASPCA Animal Poison Control (888-426-4435) immediately — do not wait for symptoms. If the ingestion was very recent and no symptoms are present, your vet may recommend inducing vomiting. If symptoms are already present, the dog needs emergency intravenous dextrose (glucose) supplementation, liver support treatment, and monitoring. Prognosis depends heavily on the dose and how quickly treatment is started.
Key Facts
- Toxic mechanism
- Causes massive insulin release → severe hypoglycaemia
- Also causes
- Acute liver failure at higher doses
- Symptom onset
- Within 15–60 minutes
- Emergency contact
- ASPCA Poison Control 888-426-4435 (24 hours)
Frequently Asked Questions
How do I know if my peanut butter contains xylitol?
Read the ingredient label carefully. Look for 'xylitol', 'birch sugar', or 'E967' in the ingredient list. Do not assume a product is safe because it is marketed as natural or healthy — some natural sweetener products contain xylitol. If you are unsure, use a plain peanut butter brand with only peanuts (and optionally salt) as ingredients.
My dog ate sugar-free gum — how urgent is this?
Extremely urgent. Sugar-free gum is one of the most common sources of xylitol toxicity and can contain dangerous amounts per piece relative to a dog's body weight. Call your vet or poison control immediately — even if your dog seems fine. Induction of vomiting within 30 minutes can prevent absorption if caught quickly enough.
Is xylitol dangerous for cats?
Cats do not appear to be affected by xylitol in the same way dogs are — they do not have the same insulin-releasing response to xylitol. The evidence for feline xylitol toxicity is very limited compared to dogs. However, since cats are obligate carnivores and should not be eating sweets anyway, avoiding xylitol in cat products is still prudent.
Medical disclaimer: This glossary entry is for educational purposes only and does not constitute veterinary advice. Always consult a licensed veterinarian for diagnosis and treatment of your pet's health conditions.