Dog ate chocolate, grapes or xylitol? What to do right now

Right now: five steps

1. Move your dog away from what’s left, and keep the wrapper, box, bottle or plant. The label is the most useful thing you can have.
2. Call your vet, an emergency vet or one of the two poison lines above. Call even if your dog seems fine.
3. Don’t give anything — no salt, oil, milk, food or medicine — and don’t make your dog vomit unless a vet tells you to.
4. Have the details ready: your dog’s weight, what was eaten (with the label and, for chocolate, the % cacao), how much is missing, when it happened, and any signs you’ve seen.
5. Do what the vet or poison line says. If they ask you to come in, bring the package with you.

Why the hurry, when your dog may look perfectly well? Much of what vets can do works best early. Merck’s chapters describe emptying the stomach mainly for recent exposures — within about 2 hours for chocolate — and only while the dog still shows no signs, and its grape chapter recommends prompt treatment for dogs that still seem normal. Once signs start, treatment turns to managing the heart, the blood sugar or the kidneys. Calling early keeps every option open.

Is this an emergency? The common culprits

Every row below ends the same way, because for none of these can you rule out harm at home.

If what your dog ate isn’t in the table — a household cleaner, a plant, a pest bait — the advice is the same: call, and have the label or a photo of the plant ready.

Chocolate: why the type matters so much

Chocolate contains two related stimulants, theobromine and caffeine, called methylxanthines. Merck notes there is 3–10 times more theobromine than caffeine, and both count toward the risk. Dogs clear theobromine slowly: its half-life in dogs is about 17.5 hours, against 4.5 hours for caffeine. Signs usually start 6–12 hours after eating. Merck lists thirst, vomiting, diarrhea, a bloated belly and restlessness first; they can progress to hyperactivity, frequent urination, wobbliness, stiffness, tremors and seizures, with a racing or irregular heartbeat, fast breathing, high blood pressure and a high body temperature. Merck also notes that the fat in chocolate products can trigger pancreatitis in susceptible dogs.

The darker the chocolate, the more stimulant per ounce. Merck’s reference table runs from cocoa powder (the most concentrated) through unsweetened baker’s chocolate, semisweet and dark, down to milk chocolate; white chocolate has almost none. For a bar with a cacao percentage on the label, Merck multiplies its baker’s chocolate figure by that percentage. USDA’s FoodData Central lists 802 mg of theobromine and 80 mg of caffeine per 100 g of 70–85% dark chocolate, which works out to about 250 mg per ounce. Our calculator shows both figures, so you see a range rather than one falsely precise number. Merck adds that the stimulant content of chocolate varies naturally between cocoa beans and between brands, another reason a single figure would claim more precision than exists.

Two less obvious sources: cocoa powder in baking, which is the most concentrated form of all, and garden mulch made from cocoa bean hulls. Merck notes that some hull mulches have had the stimulants removed during manufacturing and some haven’t, so call for mulch as you would for chocolate.

If you don’t know the type, or it was a mix, our calculator counts it as baker’s chocolate, the most concentrated solid form, so the estimate errs on the side of calling.

The published thresholds, and four worked examples

Vets turn the amount into a dose: the milligrams of theobromine plus caffeine per kilogram of the dog’s body weight. Merck gives these levels for dogs. The numbers in the first column are milligrams of theobromine and caffeine combined, per kilogram of body weight.

Merck also notes that individual dogs vary in how sensitive they are. That’s why our calculator reads the risk band from the high end of the range, and why every result says to call.

Example 1 — dark chocolate. A 10-lb (4.5-kg) dog eats 1 oz (28 g) of a 70% dark chocolate bar. At 250 to 307.6 mg per ounce, that is a dose of 55.1–67.8 mg/kg of theobromine and caffeine, which reaches the level where seizures are possible, so call now.

Example 2 — milk chocolate. The same 10-lb dog eats 1 oz of milk chocolate instead: about 14.1 mg/kg of theobromine and caffeine, below the 20 mg/kg level at which Merck says mild signs may occur, and you should still call because dogs vary and so do chocolate products.

Example 3 — cocoa powder. A 20-lb (9.1-kg) dog licks up 1 tablespoon of unsweetened cocoa powder (5.4 g, USDA’s weight for a tablespoon): 13.6–16.9 mg/kg of theobromine and caffeine, below the first threshold, and still a reason to call.

Example 4 — unknown chocolate. A 10-lb dog eats 1 oz of chocolate you can’t identify. Counted as baker’s chocolate, the dose is 86.2–97.0 mg/kg of theobromine and caffeine, in the seizure range, so call now and look for the wrapper.

For scale, Merck lists about 1 ounce of milk chocolate per pound of body weight as potentially lethal. Signs start at a small fraction of that, so the size of the dog and the darkness of the chocolate matter as much as the size of the bar.

Grapes and raisins: no amount is known to be safe

Grapes, raisins and Zante currants (all Vitis) and tamarinds have caused sudden kidney failure in some dogs. Most affected dogs vomit or have diarrhea within 6–12 hours; other signs include lethargy, loss of appetite, weakness, belly pain, drinking more, dehydration and shivering. Kidney failure can follow within 24–72 hours, and Merck notes that once a dog stops making urine, most die or are euthanized. Early treatment is the point of calling straight away.

The likely culprit is tartaric acid. In a 2021 letter in the Journal of the American Veterinary Medical Association, authors from the ASPCA Animal Poison Control Center proposed tartaric acid and its salt, potassium bitartrate (cream of tartar), as the toxic principles in grapes, after dogs that ate cream of tartar developed similar kidney injury. Merck now names tartaric acid as a proposed cause and explains that dogs excrete such acids poorly.

The amount in grapes varies with the grape, the growing conditions and ripeness, so effects vary from dog to dog. That is why no amount of grapes or raisins is known to be safe, and why our calculator gives no number for them, only the call. True currants of the genus Ribes have not been linked to kidney injury, but if you aren’t sure which kind it was, call. Raisins also hide in breads, cookies, cereal bars and trail mix, so check the ingredients of anything your dog got into. For cats and ferrets, Merck mentions anecdotal reports of kidney failure after grapes or raisins but no published cases; call for them too.

Xylitol: sugar-free can be the most urgent

Xylitol is a sweetener in sugar-free gum, candy and mints, some peanut butters and baked goods, toothpaste and other oral-care products, chewable vitamins and supplements, and sugar-free liquid medicines; Merck also lists sunscreens, cosmetics, deodorants and hair products. In dogs it triggers a rush of insulin. Merck says signs of low blood sugar — vomiting, weakness, wobbliness, lethargy, seizures — can start within 30 minutes, or be delayed up to 12–18 hours when it is in something that slows absorption, such as some gums. Signs of liver injury may not show for 24–48 hours, although blood tests can pick up liver changes within 4–12 hours. In one study Merck cites, 62.5% of dogs that showed signs of liver injury died or were euthanized despite aggressive treatment, which is why vets treat a known xylitol exposure as urgent before any sign appears.

Merck ties the risk of low blood sugar and, in some dogs, liver failure to the dose swallowed, but you can’t work out the dose from a pack of gum at home, so any known xylitol is a reason to call now.

Check the ingredient list on anything marked sugar-free, and keep those products out of your dog’s reach.

Onions, garlic, macadamia nuts and lilies

Onions, garlic, leeks and chives damage red blood cells. Merck says garlic is 3–5 times more potent than onion, and notes that dried flakes, powders and soup mixes cause most cases. Merck explains that damage to red blood cells starts within 24 hours, but the anemia usually shows only 3–5 days later, as weakness, pale or yellow gums, fast breathing and collapse — so call when it happens rather than when signs appear. Cats are even more sensitive than dogs: Merck reports poisoning in cats after less than a teaspoon of cooked onion.

Macadamia nuts have caused weakness, vomiting, wobbliness, tremors and overheating in dogs, usually within 12 hours. Call.

Lilies matter if you also have a cat. FDA warns that every part of a true lily or daylily — leaves, flowers, pollen and even the vase water — can cause fatal kidney failure in cats in less than 3 days. Dogs that eat lilies may get a stomach upset but don’t develop kidney failure. If a cat may have touched a lily, call right away and take the plant or a photo of it.

Human medicine: call, and give nothing

FDA’s list of dangerous items for pets includes medicine meant for people, unless your veterinarian directs it. Pain relievers such as aspirin, ibuprofen and naproxen may harm pets, and acetaminophen is fatal to cats. Never give human medicine to a pet unless your vet tells you to, and never try to treat a poisoning with something from the medicine cabinet. The same list covers medicine meant for another pet: a dog’s flea and tick product can be dangerous for a cat, and a pill from one animal’s prescription is not a treatment for another. If your dog chewed a bottle or blister pack, call with the package in hand so the poison line can see the drug and strength.

What to tell the vet or poison line

Having these ready makes the call faster, and the person on the line can give better advice when the details are exact. A photo of the label on your phone works if you have to leave the package behind. Note down:

• your dog’s weight (a recent number from the vet’s records is fine);
• the product’s name and label — for chocolate, the type and any % cacao;
• how much is missing, as best you can tell, and the size of the package;
• when it was eaten, or the earliest and latest it could have been;
• any signs so far: vomiting, restlessness, drinking a lot, shaking, weakness;
• other health problems or medicines your dog takes.

Some online calculators call a dangerous chocolate dose mild or give grapes no warning at all; a number on a screen never outranks a call to someone who can treat your dog.

Next step

If it was chocolate, our dog chocolate toxicity calculator turns the type, amount and weight into the dose range above, with the call-now numbers first. For anything else, or if you aren’t sure, skip the calculator and call your vet or a poison line now. Later, when things are calm, our cost of owning a dog page can help you plan for the next unexpected vet bill.