Grape & Raisin Toxicity Calculator for Dogs
Estimate the potential risk level based on your dog's weight and the amount consumed.
How to Use This Calculator
To determine the potential risk, enter your dog's current weight and choose the unit (lbs or kg). Select whether they consumed fresh grapes or dried raisins. Finally, enter the estimated weight in grams of the fruit consumed. One average grape weighs approximately 5 grams, while one raisin weighs approximately 0.5 grams.
Why are Grapes and Raisins Toxic?
Recent veterinary research suggests that tartaric acid and potassium bitartrate found in grapes and raisins are the primary toxic agents. These substances can cause acute renal (kidney) failure in dogs. Unlike some other toxins where the dose is strictly weight-dependent, grape toxicity can be idiosyncratic—meaning some dogs may suffer severe reactions from very small amounts, while others may seem unaffected. However, higher doses statistically increase the risk of fatality.
Toxicity Thresholds Used
Veterinary toxicologists often use specific benchmarks to determine the severity of exposure:
- Grapes: The lowest reported toxic dose is approximately 0.3 oz per pound (19 grams per kg).
- Raisins: Because they are concentrated, the toxic dose is much lower, approximately 0.05 oz per pound (3 grams per kg).
Common Symptoms of Grape Poisoning
Symptoms usually appear within 6 to 24 hours after ingestion. Watch for:
- Vomiting and/or diarrhea (often within hours)
- Loss of appetite and lethargy
- Abdominal pain or tenderness
- Dehydration (panting, dry nose)
- Increased thirst followed by a decrease in urination (signaling kidney shut down)
Example Calculation
If a 10kg (22lb) dog eats 40g of raisins:
1. The toxic threshold for raisins is 3g per kg.
2. Toxic dose for this dog: 10kg x 3g = 30g.
3. Since 40g was consumed, this exceeds the lowest reported toxic dose, putting the dog in the High Risk category.
Emergency Action Plan
If your dog has ingested any amount of grapes or raisins, do not wait for symptoms to appear. Kidney damage may already be occurring by the time you see signs. Contact your veterinarian immediately. They may advise inducing vomiting if the ingestion was recent (within 2 hours) or starting aggressive fluid therapy to protect the kidneys.