An Update on Grape and Raisin Toxicity in Dogs

What part of the grape is toxic to dogs?

The specific pathophysiology (mechanism as to how it causes disease) of grape and raisin toxicity has not been fully understood yet. Initially, it was thought to be due to a mycotoxin (a toxin found in fungal growths) that causes kidney damage when ingested. It has also been speculated that the salicylate content naturally found in grapes and raisins causes a decrease in proper blood flow to the kidneys resulting in kidney damage.

More recently, it is thought that the tartaric acid in grapes is the main culprit of its kidney toxicity properties. Veterinary toxicologists at the ASPCA Animal Poison Control Center are currently working on a study involving the toxic aspects of tartaric acid in grapes. It’s important to note here that this study came about when examining the toxic components of homemade playdoh containing cream of tartar as a main ingredient. An important reminder for parents, that while playdoh may be non-toxic to humans, it should never be assumed safe for our pets!

Are all types of grapes and raisins poisonous to dogs?

Other food hazards, while toxic in dogs, are only dangerous when certain parts are ingested. For example, apple seeds contain high amounts of cyanide which can be toxic to dogs when ingested, but the body of the apple is generally safe to give. So as long as you don’t give apple cores, these can be tasty snacks for your pet dog.

In grapes, however, it is believed that the entire fruit is toxic. Even the seedless ones can cause kidney failure when ingested. Since the mechanism of toxicity has not been fully understood yet, ingestion of grapes or raisins, regardless of the variety or type, can potentially cause toxicity signs.

Food products that contain grapes and raisins, such as bread, cookies, granola mix, and cereals, can also be potential sources of toxicity. On the other hand, beverages derived from these fruits, such as grape juice and wine, don’t usually cause signs of toxicity.

My dog only ate one grape. Should I be worried?

There is no well-established toxic dose of grapes for dogs. The amount of grapes that can cause toxicity signs in dogs has been recorded to be as low as 0.3 ounces of grapes per pound of body weight. For raisins, the toxic dose can be as little as 0.05 ounces of raisins per pound of body weight.

These amounts, however, can be variable as there are dogs that are highly sensitive to grape toxicity at a dose significantly lower than the values mentioned, and there are dogs that can tolerate higher doses.

As a general rule, if your dog has eaten grapes or raisins, veterinary intervention is needed regardless of how much was eaten. It is very important to have your dog checked by a veterinarian if ingestion occurs, even if there are no signs of toxicity. Kidney failure brought on by grape toxicity may not be treatable if detected too late.

My dog accidentally ate grapes. What should I do?

If you think your dog has eaten grapes or raisins, it’s best to contact your vet or bring your dog to the nearest emergency clinic. If ingestion happened within the past 2-3 hours, your vet will be able to give your dog medication to induce vomiting. The goal is to remove as many of the ingested grapes as possible before they have been digested.

Your vet may also recommend giving the dog activated charcoal to minimize the absorption of toxins that have already made it into the intestines. Your dog may be hospitalized for IV fluid support and monitoring for 2-3 days. Blood tests can be performed to monitor the kidneys during this time.

What are the signs of grape poisoning in dogs?

Grape toxicity causes kidney failure in dogs. Signs associated with it are mainly those that develop when there’s kidney insufficiency. These symptoms are usually acute and develop within 24 hours after ingestion. Initial signs may include decreased appetite, weakness, and a decrease in appetite.

Severe signs of kidney failure appear around 24-48 hours after ingestion and may include nausea, uremic breath, abdominal pain, excessive urination, and water intake.

Eventually, as the kidney damage becomes more severe, the dog’s kidneys will not be able to produce urine and filter toxic substances in the blood. Kidney failure can also lead to severe anemia since the production of erythropoietin (the hormone responsible for stimulating red blood cell production) is severely compromised when there’s a loss of kidney function. When kidneys start to shut down due to grape toxicity, the prognosis is often poor and irreversible.

What is the treatment for grape toxicity in dogs?

Grape toxicity is serious and can be fatal if not treated properly and immediately. As mentioned above, the first step in treating grape or raisin toxicity is to reduce the absorption of toxic compounds either by inducing vomiting and/or by giving activated charcoal to act as an adsorbent.

However, induced vomiting and activated charcoal treatment do not eliminate the absorption of the toxic substances, and hospitalization is often needed for intensive care and patient monitoring. The main goal of treatment for grape toxicity is to minimize the damage to the kidneys as much as possible. This usually includes aggressive intravenous fluid therapy and support to protect the kidneys.

Control of clinical signs like vomiting, nausea, and increased blood pressure is also an important component of treatment. Giving nutrition through feeding tubes may be indicated for dogs that have no appetite.

Grape Toxicity Prevention

Grapes and raisins, being common fruit snack choices for people, pose a high risk of ingestion for dogs. The best way to prevent toxicity is to keep these fruits completely out of reach of pets. Storing them away securely can drastically reduce the risk of grape toxicity in dogs. This can further be prevented by avoiding sharing snacks that contain these fruits with dogs as well

Read more:

Macadamia Nut Toxicity in Dogs

The Truth About Onion and Garlic Toxicity in Dogs

Everything You Need to Know About Chocolate Toxicity in Pets

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