If your dog has eaten even a small number of grapes, raisins, sultanas, or currants, this is a potential emergency. There is no safe amount—even a single grape can cause kidney failure. Call your vet or the Animal PoisonLine (01202 509000) immediately, regardless of how many were eaten or whether your dog shows symptoms.
Why Grapes Are Extremely Toxic
Grapes, raisins, sultanas, and currants are among the most dangerous foods for dogs. Unlike many toxins where a dose-dependent threshold exists, there appears to be no safe amount for any dog. The toxic compound has never been definitively identified, which means vets cannot predict which grapes will cause harm or provide safe dosage guidance.
The toxin attacks the kidneys, causing acute kidney injury (sometimes called acute renal failure). Kidney failure can be fatal. Even dogs treated aggressively with supportive care sometimes suffer permanent kidney damage or death.
What makes this toxin especially dangerous is that damage may occur silently. A dog may not show noticeable symptoms even as their kidneys are being destroyed. By the time symptoms appear, irreversible damage may have already occurred.
The Unpredictability Problem
Grape toxicity in dogs is unpredictable in two ways:
- Unknown dose threshold — The toxic dose is unknown. Some dogs appear to tolerate small amounts (though this should never be relied upon), whilst others suffer kidney failure from a single grape.
- Individual variation — Not all dogs are equally susceptible. We do not know why some dogs seem more vulnerable than others. This unpredictability means that even a tiny exposure is risky.
Because of this uncertainty, the only safe recommendation is complete avoidance.
Symptoms of Grape/Raisin Toxicity
Symptoms can appear within 24–72 hours of ingestion:
- Vomiting
- Diarrhoea
- Loss of appetite
- Lethargy or unusual tiredness
- Abdominal pain (whimpering, reluctance to move)
- Increased thirst and urination
Later symptoms (indicating kidney failure):
- Dehydration
- Reduced urination or no urination
- Oral ulcers or bad breath (signs of uraemia)
- Pale gums
- Collapse or seizures
Critical point: Early symptoms may be mild and non-specific. Some dogs do not show obvious symptoms until substantial kidney damage has occurred. This is why calling your vet immediately is essential, even if your dog seems fine.
What to Do If Your Dog Eats Grapes or Raisins
Immediate steps:
- Call your vet or the Animal PoisonLine (01202 509000) immediately — do not wait for symptoms
- Have the following information ready:
- Type of fruit (grapes, raisins, sultanas, currants, or grape juice)
- Approximate number eaten (if known)
- Time of ingestion
- Your dog's weight and age
- Do not induce vomiting unless specifically instructed by your vet (though vomiting within 4–6 hours may be beneficial in this case, so ask)
- Your vet will likely recommend:
- Induced vomiting if within the appropriate timeframe
- Blood tests and urinalysis to check kidney function
- Activated charcoal
- Aggressive supportive care (intravenous fluids to flush the kidneys, medications, monitoring)
- Even if your dog seems fine, follow your vet's advice for monitoring and follow-up bloodwork
Do not assume that because your dog ate only one or two grapes, the situation is not serious. A single grape has caused kidney failure in some dogs. Always contact your vet immediately, no matter the quantity eaten.
Prognosis and Recovery
The outcome depends on:
- How quickly treatment was started
- How much was ingested
- The individual dog's susceptibility
- How aggressively the kidneys were damaged
Dogs treated within 24–48 hours of ingestion have better outcomes than those treated later. However, even with aggressive treatment, some dogs develop permanent kidney damage or do not survive.
Some dogs recover completely with no lasting effects. Others develop chronic kidney disease that requires lifelong management. A small number do not survive despite treatment.
This is why prevention is absolutely critical. Never expose your dog to any amount of grapes or raisins.
Prevention and Safe Foods
Keep grapes and raisins out of reach:
- Store fresh grapes in the fridge, not on counters
- Keep dried fruits (raisins, sultanas, currants) in sealed cupboards
- Be especially vigilant about:
- Lunchboxes with dried fruit
- Breakfast cereals containing raisins
- Baked goods and energy bars with dried fruit
- Fruit salads and desserts
- Christmas pudding and mince pies
- Chocolate-covered raisins or grape-based sweets
- Educate children and visitors never to give your dog any fruit without permission
Safe fruits for dogs include:
Apples (without seeds), bananas, blueberries, watermelon (without seeds), strawberries, and oranges (without seeds or skin). Always remove pips, seeds, and stones before offering any fruit.
The SafeBowl app can instantly tell you whether any food or fruit is safe for your dog. If you're ever unsure, check the app before offering anything new.
SafeBowl checks any food in seconds — personalised to your dog's breed, weight, and allergies. Download SafeBowl free.