My dog ate grapes or raisins, what should I do?

The Merck Veterinary Manual names tartaric acid as one proposed toxic principle in grapes, raisins and tamarind. Dogs excrete organic acids poorly, so it can build up in the cells of the kidney tubules. ASPCA Animal Poison Control says the same: since dogs are not able to process tartaric acid, eating grapes or raisins can lead to kidney damage.

The amount of tartaric acid in the fruit varies, which Merck says is why the effects after eating are so variable. PDSA puts it plainly for owners: the toxic amount differs between dogs and can be very small, so some dogs become unwell after eating only a little. That is why vets treat every grape as a possible poisoning, and why no page you read should tell you a number of grapes that is safe.

Tamarind belongs on the same list. Merck reports that tamarind ingestions have also resulted in kidney failure in dogs, which matters in India, where imli is in sambar, rasam, chutneys and pani puri water.

If you get there soon after your dog ate the fruit, the vet will usually try to empty the stomach. PDSA lists an injection to make the dog vomit, if given quickly, then activated charcoal to soak up what is left. Merck says prompt decontamination is the recommended treatment for a dog that is not yet showing signs.

Next comes support for the kidneys. Merck recommends a drip of intravenous fluids for at least 48 hours, especially after a large amount or if diarrhoea starts within 12 hours, with kidney function and fluid balance checked throughout. PDSA notes that kidney problems can take a few days to appear, which is why repeated blood tests are part of the plan.

The outlook depends on time. PDSA says dogs treated quickly are likely to make a full recovery without ongoing problems. Merck is blunt about late cases: once a dog stops making urine, most dogs die or are put to sleep unless dialysis is available.

Keep grapes, kishmish and tamarind in closed containers above counter height, and ask family, guests and domestic help not to share sweets, cakes or chutney with the dog. PDSA notes that poisonings are most common around festive times, when these foods are everywhere, so take extra care during Diwali, Christmas and weddings. Petym's free can my dog eat this tool and the foods toxic to dogs guide list the other kitchen risks.

If someone else is looking after your dog, put "no grapes, raisins or tamarind" on the care sheet along with your vet's number. A Petym sitter follows the pet's plan as the owner writes it, and in an emergency calls the owner and takes the pet to the nearest 24-hour vet on the city's list.