What happens if a dog eats scallions (green onion)?

A dog that eats scallions may show poisoning, because the sulfur compounds in alliums bind to the hemoglobin in red blood cells, causing hemolytic anemia, which then leads to fatigue, rapid breathing, fast heartbeat, pale mouth and gums, jaundice, and blood in the urine or stool.

A one-time large amount or long-term feeding can damage the dog’s kidneys and even cause coma, shock, or death. Therefore, once you find the dog has eaten scallions, watch its reaction closely, and if any of these symptoms appear, take it to the vet immediately.