Can Dogs Eat Onion?
Short answer
No, onion is toxic to dogs.
According to the U.S. Food and Drug Administration, which names this food among those dangerous to pets, our dog rating is toxic. Portion guidance: None. Watch for: Lethargy, pale gums, vomiting, weakness, reddish urine. The same food is rated toxic for cats, so multi-pet households should not assume the dog rating transfers. Ask your veterinarian about your own animal.
No. Onion is toxic to dogs.
One of the most common pet poisonings; onion powder especially concentrated
Food-safety rating slip
Dogs can-eat rating TOXIC Onion
TOXIC · #12/160 hazard · Vegetables
- LEVEL toxic
- RANK #12/160
- DOC #13/160
- CAT toxic
- SHARE 16% haz
- RISK 3 risks
- SYMP listed
- PHOTO Asparagus
Category photo peer: Asparagus (safe)
Onion ranks #12 of 160 foods by dog hazard band (toxic) and #13 of 160 by documentation depth in PlainPetFood's archive. Cats: toxic. Band scores in the chart are ordinal (toxic=4 → safe=1), not clinical doses. Read with this food →
Category standing
Toxic on both the dog and cat charts
Dogs and cats share a toxic rating for Onion. Inside vegetables, 4 of 25 dog ratings are toxic. This is a household-wide keep-away, not a species-specific quirk.
Source for this food: U.S. Food and Drug Administration, which names it among the foods dangerous to pets. Portion, preparation and symptom detail on this page is our own editorial guidance.
Portion & Preparation
- Recommended Portion
- None
Risks & Warnings
- ⚠ Thiosulfates cause Heinz body anemia
- ⚠ All forms toxic: raw, cooked, powdered
- ⚠ Even small amounts dangerous
Warning Signs
Lethargy, pale gums, vomiting, weakness, reddish urine
If your dog shows these symptoms, contact your vet or call ASPCA Poison Control: 888-426-4435
Also Safe for Cats?
Cats are more sensitive than dogs; tiny amounts can be fatal
Full cat safety guide for Onion →🚨 Pet Poison Emergency
ASPCA Animal Poison Control
888-426-4435
24/7, consultation fee may apply
Other Vegetables for Dogs
Read our methodology - how this data is sourced, computed, and verified.
PlainPetFood publishes an editorial food-safety compilation. When the FDA or ASPCA Animal Poison Control Center names a food as dangerous, that food's page links the source; other ratings are identified as editorial guidance. Its dog rating, portion, preparation notes and warning signs are rendered from the food-safety archive; a named FDA or ASPCA source is linked above when that authority names this food. See our editorial standards & corrections policy, report a correction, the methodology behind these numbers, or contact the editorial team. Data current as of August 29, 2026.