Onion

Toxic

Verdict

Never — destroys red blood cells.

Toxic principle: thiosulfate, organosulfur compounds
Source: ASPCA

Verdict

Onions in all forms — raw, cooked, dehydrated, or powdered — contain thiosulfates and organosulfur compounds that destroy a dog's red blood cells, causing hemolytic anemia. Powdered onion is especially dangerous because it is more concentrated. Repeated small exposures accumulate and can be just as harmful as one large dose.

Symptoms to watch for

  • pale gums
  • lethargy and weakness
  • rapid breathing
  • vomiting and diarrhea
  • reduced appetite
  • reddish or brownish urine

What to do

Call your vet. If ingestion was recent, your vet may induce vomiting. Blood tests may be needed to assess red blood cell damage. Avoid all onion-containing foods including soups, gravies, and baby food.

📞 US ASPCA Animal Poison Control: 888-426-4435

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Not veterinary advice. Always consult your vet.