Why Dogs Can't Eat Grapes

Medically Reviewed by Vanesa Farmer, DVM on January 04, 2022
3 min read

Grapes and raisins are highly toxic for dogs, regardless of breed, age, or gender. There is ongoing research about why that is.

There isn't a safe amount of grapes or raisins that your dog can consume. 

Why Can't Dogs Eat Grapes?

Grape toxicity is linked with kidney damage. Eating the fruit can result in sudden kidney failure and even death.

The toxic substance in grapes is unknown, but dogs cannot metabolize tannins, flavonoids, and monosaccharides from grapes. This could be the primary reason for grape toxicity in dogs.

When dogs eat grapes of any kind and in any form, they are at risk of kidney (renal) failure. All types of grapes, whether cooked, seedless, peeled, dried, or fresh, are toxic to dogs, even in small amounts.

You should also avoid giving your dog any grape products such as raisins, juices, jelly, or jam. 

What Should You Do If Your Dog Eats Grapes?

Since there isn't a well-established toxic dose of grapes for dogs, even very low amounts of it could be harmful to your pet. For example, an amount as low as 0.3 ounces of grapes per pound of body weight could also cause various symptoms of food toxicity. 

If your dog consumes even tiny amounts of grapes, you should contact your veterinarian as soon as possible. They may be able to induce vomiting so your pet is in the clear instead of waiting for serious symptoms that can be fatal. Keep an eye out for serious symptoms such as increased blood pressure, nausea, and vomiting. 

If you are unaware of the food product that your dog has consumed, it is wise to induce vomiting. However, if your dog has trouble breathing or exhibits any signs of distress, you should visit the vet as soon as possible. 

Your dog will need prompt care since there isn't an antidote for grape poisoning. The veterinarian can induce vomiting just after ingestion. It will help remove the grapes from the dog's system. Your vet may also suggest giving your dog activated charcoal to help minimize the absorption of toxins in the intestines.

Acute symptoms develop within 24 hours of eating the fruit. Initial signs of grape toxicity include weakness and loss of appetite. 

Severe signs of kidney failure are noticeable 24 to 48 hours after eating the fruit and include abdominal pain, nausea, and uremic breath (fishy odor). Here are some other signs of grape poisoning:

  • Vomiting
  • Anorexia
  • Diarrhea 
  • Lethargy
  • Increased thirst
  • Excessive urination
  • Anuria (no longer peeing)
  • Dehydration
  • Mouth ulcers
  • Coma
  • Seizures
  • Oliguria (decreased urination)

If you suspect that your pet has eaten grapes or raisins and you observe any of these symptoms, you should take your dog to the hospital as soon as possible.

Grapes, raisins, currants, and sultanas should never be fed to dogs. You should also make sure your dog does not consume raisin bread, grape juice, or grape jam and jelly. Be aware that some protein bars contain raisins, making them a source of toxicity to your dog.  

The best way to prevent grape toxicity in dogs is to keep these food items away from your pet.

Make sure that family members and friends visiting your house are aware of the risk of giving grapes or grape products to dogs.