Grape and Raisin Poisoning in Dogs
Grapes, raisins, currants and sultanas can cause serious poisoning and acute kidney injury in dogs.
Why are these fruits dangerous?
Grapes and their dried forms can cause severe kidney damage in some dogs. Tartaric acid has been proposed as the substance responsible, but the exact way the poisoning occurs is not fully understood.
The concentration of the substance may vary between individual fruits, varieties and levels of ripeness. Dogs also appear to vary considerably in their sensitivity.
Potentially dangerous foods
Poisoning may follow the consumption of:
- Red, green, black, seeded or seedless grapes
- Raisins
- Sultanas
- Dried currants made from grapes
- Hot cross buns
- Fruit cake, Christmas cake and mince pies
- Raisin bread, biscuits and cereal bars
- Trail mix and cereals containing dried fruit
- Chocolate or confectionery containing raisins
- Grape pressings left during wine production
The currants used as dried fruit in baking are usually small dried grapes and should be treated in the same way as raisins and sultanas.
What to do
- Remove any remaining fruit or food from your dog’s reach.
- Telephone your veterinary practice immediately, even if your dog appears completely well.
- Tell the vet what was eaten, approximately how much and when it happened.
- Have the packaging or ingredient list available if the fruit was contained in another food.
- Tell the vet your dog’s approximate weight, age and any existing health conditions.
- Follow the veterinary practice’s instructions and attend without delay if advised.
Do not give salt, hydrogen peroxide, mustard, milk or another home remedy to make your dog vomit. These treatments can cause additional poisoning or injury.
Possible symptoms
A dog may initially appear well. Early symptoms can develop within several hours and may include:
- Vomiting
- Diarrhoea
- Reduced appetite
- Lethargy or weakness
- Abdominal discomfort
Signs associated with developing kidney injury may include:
- Continued vomiting or diarrhoea
- Excessive thirst
- Passing unusually large amounts of urine
- Dehydration
- Increasing weakness and lethargy
- Unpleasant or ammonia-like breath
- Passing very little urine or no urine
- Tremors, seizures or collapse in severe cases
Veterinary treatment
There is no specific antidote. If ingestion was recent, your vet may induce vomiting safely at the surgery to remove the fruit from the stomach.
Further treatment may include activated charcoal, intravenous fluids, anti-sickness medication and careful monitoring of kidney function and urine production.
The treatment required will depend on what was eaten, the time since ingestion, the dog’s health and the results of blood and urine tests.
Diagnosis and monitoring
There is no single test that confirms grape or raisin poisoning. Diagnosis is usually based on a known or suspected ingestion together with the dog’s symptoms and test results.
Your vet may carry out blood and urine tests when the dog first arrives and repeat them over the following days. Initial results can be normal, which does not necessarily mean that kidney damage will not develop later.
Outlook
The outlook is generally better when veterinary treatment starts before symptoms or kidney abnormalities develop.
If a dog develops severe kidney failure and stops producing urine, the prognosis is poor. Dogs that recover from an acute kidney injury may require further monitoring because some can be left with reduced kidney function.
Prevention
- Keep grapes and dried fruit in cupboards or containers that your dog cannot reach.
- Check the ingredients of cakes, breads, biscuits, cereals and snack bars before offering any to your dog.
- Take particular care around Christmas and Easter when fruit cake, mince pies and hot cross buns may be accessible.
- Make sure handbags, shopping bags, lunchboxes, bins and compost containers cannot be accessed.
- Ask children and visitors not to give your dog grapes or food containing dried fruit.
- Do not use grapes or raisins as treats.