What makes xylitol toxic?
Xylitol is a sugar alcohol used in some sugar-free gum, sweets, baked goods, dental products, supplements and other products. In dogs it can trigger a rapid release of insulin, causing hypoglycemia, or dangerously low blood sugar. Larger exposures can also cause acute liver injury and problems with blood clotting. This is a species-specific danger: a product marketed as suitable for people is not necessarily safe for a dog.
Labels may use the term birch sugar. The amount per piece of gum or serving varies greatly, so one brand's concentration cannot be assumed for another. Some products contain other hazards or ingredients that slow absorption. Collect the wrapper, product name and number of pieces missing. Do not wait to see whether the dog is sick. A prompt call after known xylitol exposure is important even when the dog is walking, eating and behaving normally.
Toxic dose by body weight
Veterinary references commonly use approximately 0.1 g/kg, or 100 mg/kg, as a hypoglycemia concern; effects have been reported around 0.075 g/kg, or 75 mg/kg. Exposures around or above 0.5 g/kg, or 500 mg/kg, raise concern for liver injury. These are clinical assessment values, not guarantees of safety below them or certainty of liver failure above them. Product concentration and the maximum credible ingestion matter.
Published dose reference: Merck Veterinary Manual — xylitol; Pet Poison Helpline - Xylitol; Pet Poison Helpline — xylitol.
| Dog weight | At 75–100 mg/kg | At 500 mg/kg |
|---|---|---|
| 5 kg / 11 lb | 375–500 mg / 0.375–0.5 g xylitol | 2,500 mg / 2.5 g xylitol |
| 10 kg / 22 lb | 750–1,000 mg / 0.75–1 g xylitol | 5,000 mg / 5 g xylitol |
| 20 kg / 44 lb | 1,500–2,000 mg / 1.5–2 g xylitol | 10,000 mg / 10 g xylitol |
Published dose reference: Merck Veterinary Manual — xylitol; Pet Poison Helpline - Xylitol; Pet Poison Helpline — xylitol.
The table is for active xylitol, not the total weight of gum, toothpaste or a baked item. If the manufacturer does not state the xylitol amount, do not infer it from the ingredient order alone. The veterinarian or poison service may be able to clarify the formulation. Count every possible missing piece and mention the packaging if it may also have been swallowed. A normal early blood glucose reading does not necessarily rule out a delayed problem.
Symptom timeline: onset, peak and duration
Low blood sugar may occur within 10–60 minutes, but onset can be delayed for several hours, sometimes up to 12–18 hours, depending on the formulation. During zero to two hours, vomiting, weakness, wobbliness, collapse or seizures can appear. Between two and twelve hours, a dog may need serial glucose checks even if the first measurement was normal or the dog briefly looks better after eating.
Liver injury can emerge over approximately 8–72 hours, and significant abnormalities may be delayed. Between twelve and seventy-two hours, clinicians watch for rising liver enzymes, reduced appetite, vomiting, jaundice and impaired clotting. There is no universal peak hour, and liver injury can occur without an obvious earlier episode of hypoglycemia. The observation period and laboratory schedule depend on the estimated dose, the product and the clinical findings.
What vets typically do
The veterinarian promptly assesses blood glucose and neurological status. A recent ingestion in an alert dog may justify controlled vomiting, but hypoglycemia and airway safety take priority. Intravenous dextrose is used when needed, often with repeated glucose measurements and adjustments. The dog may need hospitalization because a single sugar dose or meal does not establish stable glucose over the following hours.
When liver risk is significant, the team checks liver values and clotting function and may use liver-supportive therapies. Fluids, anti-nausea treatment and additional support are tailored to the dog. Severe liver failure can require blood products and intensive care. Activated charcoal binds xylitol poorly and is not a routine solution for xylitol alone; another ingredient may change the assessment. There is no over-the-counter home antidote that reliably prevents both the insulin effect and delayed liver injury.
What NOT to do at home
Do not induce vomiting without explicit veterinary advice, especially in a weak, wobbly or drowsy dog. Do not give salt, oil, charcoal or human medication. Do not pour syrup or water into the mouth of a collapsed or seizing animal. Oral sugar advice, when appropriate, must come from the clinician and is not a substitute for emergency transport or ongoing glucose monitoring.
Remove the product and call immediately with the label and possible amount. Do not wait for symptoms or assume vomiting removed every piece. Keep hands away from a seizing dog's mouth and arrange urgent care. A dog that initially seems normal can still be within a delayed hypoglycemia or liver-injury window. If the quantity cannot be determined, communicate that uncertainty rather than estimating a falsely reassuring number from the size of the package.
Prognosis and prevention
The outlook is often good for promptly treated hypoglycemia when glucose is stabilized before prolonged neurological injury. Prognosis is more guarded when severe liver injury, bleeding or persistent neurological problems develops. Dose estimates help guide monitoring but cannot predict every outcome. Follow-up testing may be needed even after the dog appears clinically recovered.
Use the clinic's recheck schedule and report renewed weakness, vomiting, appetite loss, yellow gums or eyes, or unusual bruising. Store sugar-free gum and dental products out of reach, including handbags and bedside tables. Check peanut butter, supplements and recipes before sharing them; not every sugar-free product contains xylitol, but the label must be checked. Keep a photograph of the original label when reporting an exposure, because formulations can change and a familiar brand name is not sufficient evidence.
Gum: the most common source
Sugar-free gum is one of the most common ways dogs eat xylitol. Check the ingredient list for xylitol or birch sugar; the amount per piece varies by brand and is not always printed. Count the missing pieces, keep the wrapper and call your vet straight away, even if your dog seems normal. You can estimate the dose with the xylitol toxicity calculator, and see which gum and peanut butter brands contain xylitol in our gum guide.
When to call for help
Call your veterinarian promptly after a known or suspected ingestion. ASPCA Animal Poison Control Center is available at (888) 426-4435 and Pet Poison Helpline at (855) 764-7661. These poison-control lines may charge a consultation fee. If your dog collapses, has a seizure, struggles to breathe, cannot stand or has a swollen painful abdomen, seek emergency veterinary care immediately; do not delay transport to finish reading or calculating a dose.
Have the dog's weight, the product or plant name, the maximum possible amount and the ingestion time ready. Bring the packaging or a clear photograph. The information lookup linked on this page can organize details, but it does not replace a poison-control consultation or urgent treatment. Do not induce vomiting without veterinary advice. This reference summarizes published veterinary sources; it does not establish a diagnosis or claim a new veterinary review.
What to do now
Call your veterinarian or an animal poison-control service for exposure-specific advice. Dog poison control: phone numbers, fees and when to call.