Grapes and raisins for dogs: why they are dangerous and what to do
Published by Planète Pets · managing editor: Clément Lacaille · how our guides are written
If your dog has just eaten grapes or raisins, even a few, call your vet or an animal poison helpline straight away, without waiting for symptoms — in the US the ASPCA Animal Poison Control Center, (888) 426-4435 (a consultation fee may apply), in the UK Animal PoisonLine, 01202 509 000, in France the CNITV in Lyon, 04 78 87 10 40. Note the time, what was eaten (fresh grapes, raisins, a baked good) and roughly how much. Do not make your dog vomit yourself: that is the vet’s call, and the earlier they act, the better it works. Most dogs that eat grapes do not get sick, but nobody can predict which ones will: that is why you call every time, even for a small amount.
Contents · 6 sections
Why grapes are dangerous for dogs
In some dogs, grapes (and their dried forms: raisins, currants, sultanas) cause acute kidney injury: the kidneys stop filtering properly, sometimes to the point of producing no urine at all. For years the culprit was unknown. In 2022, a team from the ASPCA Animal Poison Control Center led by Wegenast described dogs with the same kidney damage after eating cream of tartar or tamarind, two products rich in tartaric acid, like grapes (see the study). The authors conclude that tartaric acid is the likely cause. The Merck Veterinary Manual takes up this explanation: dogs clear organic acids poorly, so they build up in kidney cells.
Tartaric acid content varies a lot from one grape to the next, which explains why one dog can eat a bunch with no effect while another becomes seriously ill. The Merck Veterinary Manual gives a rough marker (more than one grape or raisin per 4.5 kg, or 10 lb, of body weight may be enough to put the kidneys at risk), but a 2024 literature review from the University of Nottingham concludes that the toxic dose remains difficult to establish from published cases. In practice, there is no amount known to be safe.
What poison centre data show
A study by Dijkman and colleagues, published in 2022 in the Journal of Small Animal Practice, followed every case reported to the Dutch Poisons Information Center in 2018 (see the study). Of 95 dogs that ate grapes, about 15% showed signs, mostly digestive (vomiting, lethargy), and only one developed kidney injury. When the vet induced vomiting within 4 hours, the fruit was recovered in 98% of cases, and still in 83% between 4 and 12 hours. An analysis of more than 31,000 emergency cases in the UK, published in 2026 by Altman and colleagues, shows that processed forms (raisins, fruit cake) are involved about twice as often as fresh grapes, that 22% of cases happen in December, and that decontamination by the vet is the factor most strongly linked to survival (see the study). Mortality in dogs was low (0.9%): calling early genuinely changes the outcome.
Signs and when they appear
| Time after eating | What may happen | What you do |
|---|---|---|
| 0 to 4 hours | Often nothing visible | Call your vet or a poison helpline: this is the window where inducing vomiting works best |
| 4 to 12 hours | Vomiting or diarrhoea (often 6 to 12 hours after), sometimes with visible pieces of grape | See a vet promptly, even if the dog seems better after vomiting |
| 12 to 24 hours | Lethargy, loss of appetite, tummy pain, thirst, shivering | The vet may put the dog on a drip and check the kidneys with blood tests |
| 24 to 72 hours | The dog passes little or no urine: established kidney failure | Emergency, day or night |
Timings from the Merck Veterinary Manual. A dog that shows nothing after a few hours is not out of the woods: blood tests, not appearance, tell whether the kidneys are affected.
Hidden grapes: what you might not suspect
Most cases do not come from a bunch of grapes but from foods where the fruit goes unnoticed. Check the ingredients before sharing anything.
- Bakery: raisin bread, fruit loaf, hot cross buns, scones, Danish and cinnamon-raisin pastries.
- Breakfast: muesli, granola, cereal bars, trail mix and dried-fruit mixes.
- Cakes and holidays: fruit cake, Christmas pudding, mince pies, panettone, oatmeal-raisin cookies.
- Savoury dishes: couscous, tagines, salads or stuffings containing raisins.
- Tartar and tamarind products: cream of tartar (used in baking and in some homemade play dough recipes) and tamarind pulp or paste caused the same kidney injury in the Wegenast study.
- Grape juice and wine: published cases mostly involve the fruit, but juice comes straight from it, and wine is dangerous anyway because of the alcohol. Same reflex: call.
On the other hand, true currants such as redcurrants and blackcurrants (genus Ribes) have not been linked to this kidney injury according to the Merck Veterinary Manual, whereas dried “currants” (Zante currants) are grapes.
Prevention at home
- Keep grapes, raisins and cereals in a closed cupboard; do not leave a fruit bowl at nose height.
- Tell children and guests: a grape is not a dog treat. For rewards, our guide to training treats gives useful pointers.
- Over the holidays, the riskiest time of year, watch the cake plates on the coffee table, along with the chocolate: see our article on the toxic dose of chocolate by weight.
- For a young dog that tastes everything, read common puppy feeding mistakes; the rest of our advice is on the dog food page.
Frequently asked questions
My dog ate a single grape, is it serious?
Usually not, but nobody can guarantee it, because sensitivity varies from dog to dog and grape to grape. Call your vet or a poison helpline: based on your dog’s weight and the time elapsed, they will tell you whether you need to come in.
Are raisins more dangerous than fresh grapes?
A raisin is smaller and more concentrated, so a dog can easily swallow a lot of them. The data do not point to a safe form: the 2026 UK study even found higher mortality after fresh grapes than after processed forms. Either way, you call.
My dog ate grapes yesterday and seems fine, should I still see a vet?
Yes, call anyway: kidney injury can develop between 24 and 72 hours with no obvious sign at first. The vet may suggest a blood test to check kidney function.
Should I make my dog vomit after eating grapes?
Not yourself: salt and hydrogen peroxide given at home are dangerous. The vet uses a suitable drug, and can still do so usefully several hours after ingestion.
An accessory from our shop for this use: 1.5 L anti-splash water bowl with floating disc (€37.90) · the whole shop
This guide is part of Planète Pets’s Dogs universe. Our advice is general in nature: for any health concern, your veterinarian remains the only reference.
