Most dogs will eat anything that falls to the ground -- onions included. In any form, onions are dangerous to canine health and can be deadly if medical conditions aren't treated. Dogs may develop health problems by eating onions one day or by eating small amounts of onions over time.
Health Risks of Onions
Onions pose a significant health risk for dogs. When dogs eat too many onions, they risk developing hemolytic anemia, a condition where their red blood cells die. If the anemia is not treated, the dog can die.
Health risks of onions are the same whether your pup eats the onions raw or cooked. Not only do different kinds of onions -- such as yellow, white or red -- pose a health risk, so do onion-flavored items. Foods and spices including onion powder, onion soup mix and onion-flavored snack chips could harm your pooch. It doesn't mean you can't eat sour cream and onion chips, just make sure your pal can't reach the chip bag.
Signs to watch for include panting, an increased heart rate, vomiting and bloody urine. Onions cause gastrointestinal upset in dogs, so you may hear some tummy gurgles or see drooling. Telltale signs that your dog got into onion-flavored snacks or soup mixes include empty snack bags, packaging or wrappers on the floor. If your dog ate raw onions, onion skin or peel may be present on the floor.
In general, dogs will experience onion toxicity if they eat 0.5 percent of their body weight in onions, according to "Veterinary Technician" magazine. So a 50-pound dog will experience onion toxicity after eating 0.25 pounds or 4 ounces of onion. If you know your dog ate onions, contact your nearest emergency vet to begin treatment as soon as possible. For a two-hour window after your pup eats onions, the vet can induce vomiting to expel onions from his system. Afterward, the pet needs veterinary care and red blood cell monitoring. Treatment may require a blood transfusion to help restore your pet's red blood cells to health.
By Elton Dunn
About the Author
A successful website writer since 1998, Elton Dunn has demonstrated experience with technology, information retrieval, usability and user experience, social media, cloud computing, and small business needs. Dunn holds a degree from UCSF and formerly worked as professional chef. Dunn has ghostwritten thousands of blog posts, newsletter articles, website copy, press releases and product descriptions. He specializes in developing informational articles on topics including food, nutrition, fitness, health and pets.