Deadly Fruit: Grapes and Raisins are Toxic to Dogs

Introduction

Grapes and raisins are popular snack foods for humans. However, these fruits can be dangerous and even deadly for dogs. While the toxicity is not fully understood, grapes and raisins have consistently caused kidney failure in dogs who ingest even small amounts. 

This article will cover the key facts all dog owners need to know about grape and raisin toxicity. We'll explore how much is dangerous, what signs of poisoning to watch for, which breeds are most at risk, why the fruits are toxic, how the toxicity is diagnosed and treated, and most importantly, how to prevent exposure. By understanding the dangers, dog owners can take steps to keep their pets safe.

Why Grapes and Raisins Are Dangerous for Dogs

Grapes and raisins can be extremely toxic and potentially fatal to dogs. The consumption of even a small quantity can result in acute kidney failure. The exact toxic substance in grapes has been a mystery for a long time, but recent research has shed light on the culprit. 

A recent case study was the basis for a breakthrough after a dog that consumed homemade playdough became deathly ill. The playdough contained cream of tartar, which also contains tartaric acid. The dog developed severe azotemia (high nitrogen levels in the blood) after ingesting the playdough. This led to the realization that tartaric acid and potassium bitartrate (both present in grapes) could be the toxic principles causing kidney failure in dogs.

Veterinarians from the ASPCA Poison Control Center (APCC) discovered that tartaric acid is the primary toxic component in grapes. This acid is found in varying levels in grapes, raisins, and sultanas. 

When ingested, grapes and raisins prevent the kidneys from being able to filter toxins out of the blood and cause vomiting, diarrhea, increased urination, lethargy, and loss of appetite. If left untreated, grape and raisin toxicity can lead to severe kidney damage and even death in as little as 24 hours. Even small amounts like a handful of raisins or a few grapes can be dangerous to dogs.

Toxicity Levels

The amount of grapes or raisins that can be toxic to dogs depends on the size and breed of the dog. Findings also link different toxicity to different types of grapes. The dog's weight, overall health, and the amount of grapes ingested are also key factors of the toxicity levels. In short, these doses and weight measurements per dog can vary drastically. They are a reference only. Even small amounts can cause kidney failure in some dogs, whereas some dogs seem unaffected. 

For larger dogs, over 0.5 ounces of raisins per pound of body weight can be toxic. This means around 9 ounces of raisins could poison a 50-pound dog. 

For smaller dogs, just 0.1 ounces per pound of body weight can cause problems. This means only 2-3 grapes or raisins could be dangerous for a 10-pound dog.

The lowest documented toxic dose is around 0.1 ounces of raisins per pound of body weight. But some dogs have developed kidney failure from even less, likely due to underlying health conditions.

The highest reported non-toxic dose is around 0.7 ounces per pound of body weight. However, this amount should not be considered safe, as sensitivity varies between dogs.

In general, the smaller the dog, the greater the risk. However, any amount has the potential to cause toxicity.

Symptoms of Grape/Raisin Toxicity

Grapes and raisins can cause rapid development of kidney failure in dogs. Within 24 hours of ingestion, dogs may begin to show the following symptoms:

⚠️Vomiting 

⚠️Diarrhea

⚠️Lethargy

⚠️Loss of appetite

⚠️Increased thirst

⚠️Abdominal pain

⚠️Dehydration

Vomiting and diarrhea can occur within a few hours of ingestion. Lethargy may follow as the toxins start to take effect. Decreased appetite, increased thirst, and abdominal pain are also common as kidney function is impaired. 

Without treatment, dogs can develop acute kidney injury leading to oliguria (decreased urine production), anuria (lack of urine production), and renal failure. Severely affected dogs may show neurological signs like tremors, seizures, and disorientation as toxins build up in the bloodstream. Ultimately, dogs can fall into a coma and die within 24-72 hours without aggressive treatment.

Breeds at Risk

The American Kennel Club states that all dog breeds can be susceptible to grape, raisin, or tartaric acid toxicity. Small breeds in particular have been reported to experience severe reactions and kidney failure after ingesting even a small amount of grapes or raisins. One theory is that smaller dogs have less body mass, so toxins become concentrated more quickly. So in the case of grape and raisin toxicity, it seems size does matter. 

Age does not seem to be a major factor, as dogs of all ages have suffered from grape and raisin poisoning. Certain genetic factors or pre-existing conditions may also play a role. This means any dog with preexisting health issues could be at a higher risk for the severity of grape or raisin toxicity. 

The bottom line is that all dogs should avoid grapes and raisins. However, small breed dogs in particular should never be given access, even accidentally, as even one grape could lead to irreversible kidney damage or failure. Owners of high-risk breeds should be especially vigilant about keeping grapes and raisins away from their dogs.

Diagnosis

Veterinarians use a combination of tests and assessments to diagnose grape or raisin toxicity in dogs. An important first step is taking a full history from the pet owner about when and how many grapes or raisins were ingested. 

Blood tests can check for elevations in kidney values like blood urea nitrogen (BUN) and creatinine, which may indicate kidney problems if elevated. Urinalysis can also check for protein in the urine, another sign of possible kidney issues. 

Veterinarians may induce vomiting if ingestion is recent to try to remove any remaining grapes or raisins from the stomach before they are absorbed. They may also administer activated charcoal to help bind up toxins. 

Imaging tests like abdominal radiographs or ultrasounds can check for abnormalities in the kidneys, such as swelling or irregularities. This helps vets assess the level of damage.

Monitoring blood work over the next 2-3 days after ingestion is also important. Vets will check to see if kidney values rise over time, which would signify kidney injury. They also monitor the dog's urine output.

Overall, vets use the dog's case history, clinical signs, bloodwork, urinalysis, and imaging to determine if grape or raisin toxicity is present and how severe it may be. Prompt veterinarian care is essential for the best outcome after ingestion.

Treatment

The main treatment for grape and raisin toxicity in dogs is to provide supportive care until the toxins are flushed from the dog's system. Vomiting is induced if the dog has recently ingested grapes or raisins, in order to prevent further absorption of toxins. 

However, the most critical part of treatment is aggressive intravenous fluid therapy to promote urination. Fluids help to flush out the kidneys and prevent kidney damage or failure. The kidneys are most at risk from grape and raisin toxicity, so closely monitoring their function with bloodwork is also essential. 

Depending on how much grape or raisin ingestion occurred and when the vet may hospitalize the dog and provide round-the-clock fluid therapy for 2-3 days. This helps dilute the toxins and allows the kidneys to excrete them safely. 

Kidney values and urine output are monitored to ensure the kidneys are functioning properly. If kidney damage or failure occurs, further treatment such as dialysis may be necessary. With prompt veterinary treatment to support kidney function, most dogs recover fully from grape and raisin toxicity.

Prevention

The most important thing is to prevent your dog from consuming grapes or raisins in the first place. Here are some tips:

Keep grapes and raisins out of reach of your dog. While most families like to have a fruit bowl easily accessible, do not leave them unattended on countertops or tables. Store grapes in a secure location your dog cannot access.

Never intentionally feed grapes or raisins to your dog as treats. While grapes and raisins are a healthy snack for humans, they can actually be a deadly option for your dog. Even small amounts can be dangerous.

Check the ingredients of any pre-packaged human foods or treats before feeding them to your dog. Some may contain grape or raisin ingredients.

When out on walks, keep your dog from eating fallen grapes off vines or on the ground. 

If you grow grape vines in your yard, consider fencing them off. Wild grape vines can often grow around more rural homes. Keep an eye out for wild vines, and any grapes that may drop seasonally. 

When visiting others, advise them not to feed grapes or raisins to your dog. Inform guests and children. Kids love to share snacks with furry family members. Be sure to have a talk, at age-appropriate times, to ensure children do not innocently share grapes or raisins with any dogs. Supervise young children closely when eating raisins or grapes around your dog. Accidental droppings can happen.

The most effective prevention is simply keeping grapes and raisins completely away from your dog. Do not feed them as treats under any circumstances. With proper vigilance, grape and raisin toxicity can easily be avoided.

Conclusion

Grapes and raisins can be extremely toxic and dangerous for dogs. Even small amounts can lead to severe kidney damage and failure. 

Some of the signs of grape and raisin toxicity include vomiting, diarrhea, lethargy, loss of appetite, increased thirst, and abdominal pain. These symptoms usually occur within 24 hours of ingestion. 

It's important to prevent dogs from consuming grapes and raisins, as they can be fatal even with early treatment. Keep grapes, raisins, and foods containing them safely away and out of reach. Be aware of early symptoms if ingestion occurs and seek veterinary help immediately. Quick action can help avoid irreversible kidney damage and potential death.

The dangers of grapes and raisins for dogs cannot be stressed enough. While the toxicity is still being researched, prevention is key to keeping dogs safe. Spread awareness and keep grapes and raisins far away from your furry friends.

If you think your dog may have eaten grapes or raisins contact the Animal Poison Control Center immediately.