In this VETgirl online veterinary CE blog, we discuss grape and raisin toxicity in dogs. Grapes and raisins (Vitis spp) have been recently associated with development of acute kidney injury (AKI) with ingestion. All types have been implemented with toxicosis, including organic grapes, commercial grapes, homegrown grapes, and seedless or seeded grapes. While the mechanism of toxicosis is unknown, there are several suspected hypotheses, including individual inability to metabolize certain components of the fruit (e.g., tannins, high monosaccharide content), the presence of mycotoxins or pesticide residues on the fruit, or salicylate-like chemicals within the grape or raisin. Common kitchen items also contain grapes, raisins, or currants in their active ingredient, including raisin bread, trail mix, chocolate-covered raisins, cereal with raisins, etc. Currently, grapeseed extract has not been associated with nephrotoxicity.
Treatment for grape and raisin ingestion includes aggressive decontamination as the first-line of therapy. Grapes and raisins seem to stay in the stomach for a prolonged period of time, and are not rapidly broken down or absorbed from the GI tract; hence, delayed emesis induction even several hours post-ingestion can still be initiated to maximize decontamination methods. One dose of activated charcoal can also be administered to prevent absorption of the unknown nephrotoxin. As there is no current veterinary peer-reviewed, scientific published toxic dose of grapes and raisins, all ingestions should be treated as potentially idiosyncratic and be appropriately decontaminated and treated.
Initially, vomiting may be observed within the first 24 hours of ingestion. Within the next 12-24 hours, clinical signs of lethargy, dehydration, vomiting, diarrhea, anorexia, abdominal pain, uremic breath, and diarrhea may be seen. Azotemia may develop within 24 hours, with hypercalcemia and hyperphosphatemia occurring first. Oliguria and anuria may develop 48-72 hours post-ingestion, at which point the prognosis is poorer. Treatment includes decontamination, aggressive IV fluid therapy, anti-emetics, blood pressure and urine output monitoring, and serial blood work monitoring (q. 12-24 hours). In severe cases, hemodialysis or peritoneal dialysis may be necessary. Asymptomatic patients that have been adequately decontaminated and survive to discharge should have a renal panel and electrolytes monitored 48-72 hours post-ingestion. Overall, the prognosis varies from good to poor, depending on time to decontamination, response to therapy, and prevalence of oliguria or anuria. While 50% of dogs that ingest grapes and raisins never develop clinical signs or azotemia, aggressive treatment is still warranted.
When in doubt, call ASPCA Animal Poison Control Center for life-saving advice!
1. Eubig PA, Brady MS, Gwaltney-Brant SM. Acute renal failure in dogs after the ingestion of grapes or raisins: a retrospective evaluation of 43 dogs (1992-2002). J Vet Inter Med 2005;19(5):663-674.
2. Gwaltney-Brant SM, Holding JK, Donaldson CW, et al. Renal failure associated with ingestion of grapes or raisins in dogs. J Am Vet Med Assoc 2001;218(10):1555-1556.
3. Morrow CMK, Valli VE, Volmer PA, et al. Canine Renal Pathology Associated with Grape or Raisin Ingestion: 10 Cases. J Vet Diagn Invest 2005;17:223-231.