Xylitol Toxicity In Dogs: What Pet Owners Should Know

Xylitol toxicity in dogs is now the second most common poisoning call, right after chocolate. Between 2015 and 2020, calls related to xylitol poisoning jumped by a staggering 108%, and many pet owners still don’t realize just how dangerous this common sugar substitute can be.

Found in sugar-free gum, peanut butter, baked goods, toothpaste, and more, xylitol offers great benefits for humans, but it has the opposite effect on dogs. Even a small amount can trigger hypoglycemia, vomiting, seizures, liver failure, or even lead to a coma.

Our veterinarian team is here to help you understand the risks and recognize the signs of xylitol poisoning in dogs, so you can act fast and keep your furry family members out of harm’s way.

What pet owners should know about xylitol

Xylitol is a sugar alcohol that was first identified in 1891 by a German chemist named Emil Fisher. The substance is found naturally in berries, plums, corn, oats, mushrooms, lettuce, trees, and other fruits, but for commercial purposes, most xylitol is extracted from corn fiber or birch trees. 

Finland was the first to produce xylitol during World War II when sucrose became unavailable. When the war ended and sucrose was available again, xylitol production was stopped, but commercial interest was revived in the mid-1970s.

Efficient and economical techniques to produce xylitol, such as using corncobs left over from ethanol production, have continued to increase xylitol’s availability. Xylitol has many beneficial properties for humans, such as: 

• Less calories — Xylitol is as sweet as sucrose, but has only two-thirds the calories.

• Low glycemic index — Xylitol, which causes a negligible insulin release in people, is a good sugar substitute for people on a low carbohydrate diet, and those concerned with the food’s glycemic index.

• Energy source for diabetics — Because xylitol doesn’t require insulin to enter cells, the substance can be used as an oral and intravenous energy source for diabetics.

• Oral care products — Xylitol prevents oral bacteria from producing acids that damage tooth surfaces, and is a popular ingredient in sugar-free gum, toothpaste, and other oral care products.

Why xylitol is toxic to dogs

Xylitol might be a safe and even beneficial sugar substitute for humans, but for dogs, it's a completely different story. The way their bodies process xylitol turns this seemingly harmless ingredient into a dangerous toxin. 

Xylitol is metabolized differently in different species. Humans, rats, rhesus monkeys, and horses metabolize xylitol in one way, while dogs, rabbits, baboons, cows, and goats metabolize the substance in another way. Little data is available on how xylitol is metabolized by cats and ferrets.

• Humans — Once ingested, xylitol is absorbed slowly over three to four hours, and the increase in insulin levels after xylitol ingestion is negligible compared with the increase after glucose ingestion.

• Dogs — Once ingested, xylitol is absorbed quickly, reaching peak plasma levels in about 30 minutes. This leads to a dose-dependent 2.5- to 7-fold increase in insulin levels compared with ingestion of an equal amount of glucose.

Small studies have been performed that indicate xylitol is not toxic to cats, but caution should be used until more is known. The safest recommendation is to avoid giving any pet xylitol.

Xylitol toxicosis in dogs: How it happens

When a dog ingests a xylitol-containing product, their pancreas mistakenly thinks the xylitol is real sugar. In response, the pancreas releases a surge of insulin to manage the “sugar” levels. However, this insulin response is exaggerated, causing a dangerous drop in blood glucose within 30 minutes to a few hours after ingestion.

In some cases, the dog may even experience uncomplicated hypoglycemia, which is when blood glucose levels fall to dangerously low levels without the presence of other complications.

Xylitol can be found in common products that contain it, such as sugar-free gum, candy, peanut butter, baked goods, and even some toothpaste. Xylitol can also be listed under different names, like birch sugar, making it essential for pet owners to carefully check labels before offering their dogs any food or treats.

Clinical signs of xylitol poisoning in dogs

Xylitol poisoning can lead to a range of clinical signs, some of which are life-threatening if not addressed immediately. The severity of these symptoms depends on the amount of xylitol ingested, and it’s crucial for pet owners to recognize them early and seek medical help right away.

Hypoglycemia

As mentioned earlier, hypoglycemia is one of the most common signs of xylitol poisoning. It happens when the dog’s pancreas releases excessive amounts of insulin in response to xylitol, causing a sharp drop in blood glucose. Symptoms include:

• Vomiting

• Disorientation

• Weakness

• Incoordination

• Tremors

• Seizures (in severe cases)

These signs typically appear within 30 minutes to an hour after ingestion. If your dog exhibits any of these symptoms, it's critical to get them to a vet immediately.

Liver damage

Higher doses of xylitol can lead to liver damage, which might not always present with hypoglycemia. Symptoms related to liver damage include:

• Jaundice (yellowing of the skin, eyes, or gums)

• Loss of appetite

• Lethargy

• Abdominal pain

• Dark urine

• Vomiting

If liver failure sets in, more severe symptoms like internal bleeding, clotting problems, and coma can occur. The prognosis for dogs with liver failure is generally poor without timely treatment.

Gastrointestinal distress

In addition to vomiting, dogs with xylitol poisoning may also experience:

• Diarrhea

• Abdominal bloating or discomfort

• Loss of appetite

These symptoms can occur even if the dog doesn’t develop hypoglycemia, and they are usually an early sign that something is wrong after ingesting xylitol-containing products.

Seizures

Seizures are a more severe sign that may develop if the dog’s blood glucose drops dangerously low due to xylitol ingestion. Seizures can be caused by the direct impact of low blood sugar on the brain. If left untreated, seizures can lead to further neurological damage or even death.

Weakness and lethargy

Dogs affected by xylitol poisoning may appear unusually tired, weak, or lethargic. This is particularly noticeable after the initial phase of hypoglycemia and could be a sign that the body is struggling to regain normal blood sugar levels.

Tremors and muscle twitching

Muscle tremors or twitching is another sign of low blood sugar. These tremors can progress to more serious issues, such as seizures, if not treated promptly.

Coma

In severe cases, if xylitol poisoning is not addressed quickly, the dog may lapse into a coma. This is often the result of extreme hypoglycemia or acute liver failure.

What to do if your dog ingests xylitol

Knowing the exact amount of xylitol your dog ingested is helpful in determining their treatment, and the sooner treatment begins, the better their prognosis. 

If you suspect your dog has ingested xylitol, the first step is to induce vomiting to remove the toxin from their stomach. The faster the xylitol is cleared from the body, the less chance it will cause further harm.

Important: Always contact your vet or an emergency animal poison control center (like the ASPCA Animal Poison Control Center) before inducing vomiting, as they can provide you with specific guidance based on your dog’s situation.

Veterinary treatment of xylitol poisoning

Once at the veterinary clinic, your dog will likely be started on an intravenous dextrose drip to stabilize their blood sugar levels. This treatment typically lasts for around 24 hours and ensures that your dog’s glucose levels remain safe during the critical period after ingestion.

The vet will also monitor your dog’s liver enzymes and blood clotting factors for 2 to 3 days, as elevated levels can signal liver damage or the risk of bleeding. In more severe cases, blood transfusions may be necessary if abnormal clotting or hemorrhaging occurs.

How to prevent xylitol toxicity in dogs

Steps you can take to safeguard your pet and decrease their xylitol ingestion risk include:

• Reading the ingredients — Before offering your pet any human food, such as peanut butter, read the label to look for xylitol. Also, avoid products labeled with words such as “reduced sugar,” “diabetic friendly,” “sugar-free,” and “cavity preventing.”

• Keeping products out of reach — Keep all gum, candies, and mints, which could contain xylitol, out of your pet’s reach, and ensure your pet can’t access your guest’s purses or coat pockets that may hold the items.

• Be prepared — Put Billings Animal Family Hospital and Animal Poison Control Center in your contact list, so you can easily reach help if your pet ingests xylitol. 

Final thoughts: Protecting your pet

Xylitol toxicity is a concerning hazard, but you can take steps to protect your pet from this deadly toxin. Should your pet ingest xylitol, however, immediately contact our Billings Animal Family Hospital team, so we can provide the care they need.