Grapes toxicity in pets

The toxic component in grapes and raisins remains unidentified, and the exact mechanism is unknown. Proposed causes include ochratoxins, pesticides, or fruit components like tannins and sugars that cannot be metabolized. All types of grapes—organic, homegrown, seedless, or seeded—have been reported as toxic, potentially causing acute kidney failure due to tubular necrosis, which can lead to anuria and death. Grape seed extract isn’t linked to toxicity, and the effects of grape juice, wine, and cooked grapes are unclear.

Clinical signs of grape and raisin toxicity in dogs are believed to be idiosyncratic rather than dose-dependent, which may explain why some dogs develop acute kidney failure (ARF) while others do not.

Gastrointestinal: Vomiting, diarrhea, abdominal pain, and loss of appetite.

Renal: Acute tubular necrosis leading to acute kidney failure (ARF), including reduced or absent urine output.

Metabolic: Hypercalcemia, hyperphosphatemia, and metabolic acidosis from uremic acids.

Neuromuscular: Rare cases of weakness and ataxia.

Decontamination: Induce vomiting within 6 hours of ingestion if there are no contraindications. Follow with a single dose of activated charcoal with sorbitol.

Supportive Care:

• IV Fluids: Administer intravenous fluids for at least 48 hours to maintain kidney function and help flush out toxins.

• Monitoring and ARF Management: If acute renal failure (ARF) symptoms appear, provide intensive care, including monitoring urine output, blood pressure, and possibly using dopamine, furosemide, or mannitol infusions as needed. Severe cases may require dialysis.

• Gastric Protectants and Antiemetics: Reduce vomiting and protect against uremic gastritis with maropitant (1 mg/kg SQ every 24 hours), an H2 blocker like famotidine, or a proton pump inhibitor such as pantoprazole or omeprazole.

Note: There is no known antidote for grape and raisin toxicity.

Due to the unpredictable metabolism of grapes in dogs, an urgent veterinary visit is essential after ingestion. With prompt decontamination and fluid therapy, the prognosis is generally good. Over 50% of dogs show no clinical signs after ingestion. However, in cases where acute renal failure (ARF) develops, the prognosis is poor to grave, especially for anuric dogs without access to dialysis. Survival is possible even in severe cases if supportive care is sustained long enough for kidney regeneration, which may take weeks to months