After dogs eat onions by mistake, they may excrete red or dark red hemoglobin in the urine, and may also experience symptoms such as vomiting and diarrhea; depression, palpitations, and splenomegaly.

You should clean your mouth immediately. If you find a dog eating onions, you should immediately check the dog's mouth to see if there are any onions that have not been swallowed and clean them up. And prevent the dog from continuing to eat, and then try to use soapy water and dilute hydrogen peroxide to induce vomiting in the dog to prevent the dog from digesting more onions and relieve the symptoms of poisoning.

Once a dog shows symptoms such as blood in the stool, blood in the urine, convulsions, and heavy breathing, it needs to go to the hospital immediately. Self-rescue is basically impossible to succeed. Therefore, when owners feed their dogs, it is best to avoid human food as much as possible.