Is it toxic to dogs?
Yes, all types of grapes, raisins, and currants are toxic to dogs. The toxicity is idiosyncratic, meaning that a dog's sensitivity cannot be predicted by breed, size, age, or prior exposure, and even a single grape can be fatal for some dogs by causing acute kidney injury.
While the exact toxic mechanism was long unknown, recent research (2021) suggests that tartaric acid is the likely culprit. For this reason, any ingestion of grapes, raisins, currants, or products containing them (like grape juice or trail mix) should be treated as a potential medical emergency. There is no known "safe" amount.
Toxic dose by dog weight
There is no established safe dose or predictable toxic dose for grapes and raisins in dogs. The toxic effect is idiosyncratic, meaning some dogs may be affected by a very small amount while others might consume more with no ill effects. Because it is impossible to know which dogs are sensitive, any ingestion is considered a risk for kidney damage.
| Dog Weight (lbs) | Dog Weight (kg) | Potentially Toxic Amount |
|---|---|---|
| 10 | 4.5 | Any amount (1+ grapes) |
| 25 | 11.3 | Any amount (1+ grapes) |
| 50 | 22.7 | Any amount (1+ grapes) |
| 75 | 34 | Any amount (1+ grapes) |
| 100 | 45.4 | Any amount (1+ grapes) |
Note: This table reflects the consensus from veterinary poison control centers that because the minimum toxic dose is unknown, any ingestion should be considered potentially dangerous.
Symptoms timeline
Symptoms of grape toxicity are often delayed, with the most severe signs of kidney injury not appearing for 24 to 72 hours after ingestion. Early decontamination within the first few hours is critical.
- 0–2 Hours: Vomiting is the most common early sign, often occurring within the first few hours. This may be followed by lethargy or hyperactivity.
- 2–24 Hours: Continued vomiting, lethargy, and loss of appetite may occur. You might also notice diarrhea and dehydration (tacky gums, sunken eyes).
- 24–72 Hours: This is the critical window for the onset of acute kidney injury (AKI). Signs include a significant decrease or complete cessation of urination, abdominal pain, excessive thirst, and continued lethargy and vomiting. This is a life-threatening stage.
- 72+ Hours: Without veterinary intervention, the prognosis becomes very poor once advanced signs of kidney failure have developed.
What to do right now
Dog poison control: phone numbers, fees and when to call.
- Remove the grapes: Immediately take any remaining grapes or raisins away from your dog.
- Call for help: Contact a veterinary poison control hotline or your veterinarian immediately. Do not wait for symptoms to appear. This is a time-sensitive toxicity.
- Do NOT induce vomiting: Do not attempt to make your dog vomit without explicit instructions from a veterinary professional. Inducing vomiting can be dangerous in some situations.
- Preserve evidence: If possible, estimate how many grapes your dog may have eaten and at what time. This information is helpful for the vet.
When to call a vet
- Call a veterinarian or poison control center immediately if you suspect your dog has eaten any amount of grapes, raisins, or currants. Even if it's just one grape and your dog seems fine, the risk of delayed kidney failure is too high to ignore.
- If your dog is showing any of the symptoms listed above, such as vomiting, lethargy, or changes in urination, seek emergency veterinary care.
How it compares to other common toxins
Grape toxicity is different from many other common food-related toxins because its effect is idiosyncratic rather than dose-dependent. Unlike chocolate, where toxicity is based on the dog's weight and the amount and type of cocoa consumed, any amount of grapes can be toxic. It is also different from xylitol, which has a very predictable, dose-dependent effect on insulin release. The unpredictable nature of grape toxicity is what makes it particularly dangerous, placing it in a similar risk category as other idiosyncratic toxins.