PoisoningDog SafetyFood

Foods toxic to dogs: onion, garlic, grapes, chocolate and more

Foods toxic to dogs include onion, garlic, grapes, raisins, chocolate, xylitol and raw dough. Merck, Pet Poison Helpline and the ASPCA say call a vet early.

··9 min readBold Magazine

Foods flagged as toxic to dogs include onion and garlic, grapes, raisins and tamarind, chocolate and caffeine, xylitol, macadamia nuts, alcohol and raw yeast dough. Each group below is flagged by at least two of the Merck Veterinary Manual, Pet Poison Helpline and the ASPCA; tamarind is listed by Merck alone. Signs can start within minutes or only after days, so if your dog has eaten any of them, phone a vet instead of waiting.

Call a vet now if your dog has eaten any of these foods, even if it looks completely well. Tell the vet what was eaten, how much, when, and your dog’s weight. Do not try to make your dog vomit unless a vet tells you to. Go to a clinic at once if your dog collapses, has tremors or seizures, has a swollen belly, retches without bringing anything up, or passes little or no urine.

What foods are toxic to dogs?

The table sets out what the sources say about each food. It leaves out amounts on purpose. Pet Poison Helpline notes that the amount eaten, the size of the animal and other factors decide what is toxic to a particular pet. Treat any amount as a reason to phone a vet.

FoodWhy it is dangerousSigns the sources list
Onion, garlic, chives, leeksDamage to red blood cells, causing anaemia (Merck, Pet Poison Helpline, ASPCA)Often delayed by days. Lethargy, weakness, pale mucous membranes, jaundice, fast breathing, vomiting, collapse (Merck, Pet Poison Helpline)
Grapes, raisins, sultanas, Zante currants, tamarindKidney injury. Tartaric acid is the proposed toxin (Merck, ASPCA)Vomiting or diarrhoea within 6 to 12 hours, then tiredness, belly pain, extra thirst. Kidney failure with little or no urine within about 1 to 3 days (Merck)
Chocolate, cocoa, coffee and other caffeineTheobromine and caffeine act on the heart and nervous system (Merck, Pet Poison Helpline, ASPCA)Vomiting, diarrhoea, thirst, restlessness, fast heartbeat, tremors, seizures. Usually within 6 to 12 hours of eating chocolate (Merck; Pet Poison Helpline says within 6 to 12 hours)
Xylitol (sugar-free gum, mints, some foods and medicines)Rapid insulin release in dogs, causing low blood sugar, and possible liver injury (Merck)Vomiting, weakness, wobbliness, lethargy, seizures, coma (Merck, ASPCA)
Macadamia nutsMechanism unknown; can affect nerves and muscles (Merck, Pet Poison Helpline)Weakness, vomiting, wobbliness, tremors, raised temperature, usually within 12 hours (Merck, ASPCA)
AlcoholEthanol is absorbed rapidly (ASPCA)Vomiting, diarrhoea, incoordination, depression, difficulty breathing, tremors, coma (ASPCA, Pet Poison Helpline)
Raw yeast doughDough expands in the stomach and yeast makes alcohol (Merck, Pet Poison Helpline, ASPCA)Retching with nothing coming up, swollen belly, lethargy, then unsteadiness, weakness, seizures (Merck, Pet Poison Helpline)

An ingredient reminder. Onion and garlic can be in curries, biryani and sambar, and raisins can turn up in biryani and festival sweets. That is a prompt to check what your dog reached, not a claim about how much of anything a dish contains. None of the sources we read name Indian dishes. Tell the vet the dish and every ingredient you know.

Are onion and garlic toxic to dogs?

Yes. Merck says the Allium family includes garlic, onions, chives and leeks, and that garlic and onions are the ones most often linked to poisoning. Pet Poison Helpline calls all of them poisonous to dogs, and the ASPCA says Allium species can damage red blood cells and lead to anaemia.

Merck reports dogs and cats affected after eating raw, cooked, dehydrated or granulated onions and garlic, most often in concentrated forms such as dehydrated flakes, powders or dry onion soup mixes. Pet Poison Helpline says some breeds are more sensitive, including the Japanese breeds Akita and Shiba Inu.

The catch is the delay. Merck says signs are generally not noticed until a lot of red blood cell damage has happened, usually a few days after exposure. A dog that seems fine on the day it ate onion or garlic is not in the clear. For recent ingestion Merck recommends early decontamination by the vet, and Pet Poison Helpline gives the outlook as excellent with early intervention and appropriate care.

Why are grapes, raisins and tamarind dangerous for dogs?

They can cause kidney failure. Merck says poisoning has been occasionally reported in dogs after grapes, raisins, Zante currants and tamarind. Pet Poison Helpline names raisins, sultanas and currants, adds grape juice, trail mix and bagels containing the fruit, and says organic and home-grown grapes can also poison.

The cause is not settled. Merck calls tartaric acid one proposed toxic principle, and the ASPCA says it is speculated to be the toxic component. Pet Poison Helpline says the toxicity is not necessarily dose-dependent and that signs can follow even small ingestions, so any amount is a reason to call. Among the sources we read, only Merck lists tamarind.

Merck says most dogs vomit or have diarrhoea within 6 to 12 hours, and that kidney failure with little or no urine develops within about 1 to 3 days. Pet Poison Helpline says it develops several days later. Once a dog has stopped making urine, Merck says survival is unlikely without dialysis, and even then the outlook is guarded. Full details: Tamarind, grapes and raisins: the kidney-failure puzzle in dogs.

What about chocolate, xylitol, macadamia nuts, alcohol and raw dough?

Chocolate and caffeine. Merck says the toxic principles are the methylxanthines theobromine and caffeine. Pet Poison Helpline says coffee grounds, coffee beans, tea bags and supplements can cause serious toxicity in dogs. Read My dog ate chocolate: what to do.

Xylitol. Merck says this sugar alcohol is used in sugar-free gum, candies, mints, peanut butter and baked goods, and is also in toothpaste, chewable vitamins and some medicines. Merck says signs can begin within 30 minutes and Pet Poison Helpline says within 10 to 15 minutes; Merck’s owner page says liver signs may not appear for 1 to 2 days, while the ASPCA says liver damage can occur within 12 to 24 hours. Check the ingredient list of anything labelled “sugar-free”. See also human medicines that are toxic to pets.

Macadamia nuts. Merck calls the syndrome typically nonfatal and says it resolves in 12 to 48 hours, while the ASPCA says recovery is expected within 24 to 72 hours. Pet Poison Helpline adds that some dogs develop pancreatitis because of the nuts’ high oil content.

Alcohol. Pet Poison Helpline says dogs are poisoned by licks of mixed drinks, beer or wine, by candies with liquor centres, and by raw bread dough made with yeast. The ASPCA says alcohol is absorbed rapidly, so prompt veterinary attention matters.

Raw yeast dough. Merck says raw dough expands in the warm, moist stomach and that yeast fermentation produces ethanol. The ASPCA and Pet Poison Helpline warn that the stomach can bloat and potentially twist, which the ASPCA calls a life-threatening emergency.

What should I do if my dog eats a toxic food?

Phone your vet or the nearest 24-hour clinic first, with the details listed above. Keep the packaging, because Pet Poison Helpline says the ingredient list and product name help the expert assessing your dog. Do not wait for signs. Merck recommends decontamination after recent onion or garlic ingestion, and in dogs that still look well after grapes, raisins or tamarind.

Do not make your dog vomit yourself. Pet Poison Helpline says to do this only if a vet or toxicology expert explicitly directs it, and Merck says at-home attempts are not recommended after xylitol. The poison hotlines these sources name are US services: VCA describes Pet Poison Helpline as based in Minneapolis and serving North America. From India, your own vet or a 24-hour clinic is the practical first call.

For everyday feeding, see our diet charts. This article is general education and cannot examine your dog. See our disclaimer and editorial policy.

Frequently asked questions

Is cooked onion or onion powder still toxic to dogs?

Merck says dogs and cats have been affected after eating raw, cooked, dehydrated or granulated onions and garlic. The sources give no reason to treat cooked onion as safe.

How long after eating grapes or raisins does a dog get sick?

Merck says most dogs vomit or have diarrhoea within 6 to 12 hours, with kidney failure developing within about 1 to 3 days. A dog that has eaten any grapes, raisins or tamarind should see a vet before signs appear.

What about avocado and dogs?

The sources flag the seed. Pet Poison Helpline says ingestion of the avocado seed can result in an intestinal obstruction, and Merck says dogs ingesting the intact pit can develop a foreign body obstruction of the gut. If your dog swallowed a pit, phone a vet.

Can garlic keep fleas away from my dog?

Pet Poison Helpline says garlic was once thought of as a home remedy for fleas, but has been shown to be ineffective and is not recommended. Garlic is also one of the Allium plants that can damage a dog’s red blood cells. Ask your vet about flea control instead.

Sources

General education, not veterinary advice for your animal. See the disclaimer and how articles are checked in the editorial policy.

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