Onion Poisoning In Dogs - Symptoms, Causes, Diagnosis ... - Wag!

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Onion Poisoning in DogsWritten By Grace ParkPublished: 06/24/2016Updated: 10/28/2021Veterinary reviewed by Michele K.What is Onion Poisoning?Allium species, including onions, garlic, leeks, and chives can be toxic to dogs in excessive amounts, or over time. Plants in this family contain organosulfur compounds which account for the distinctive odor and flavor associated with them. These compounds are metabolized into highly reactive oxidants which can damage the red blood cells (erythrocytes) of dogs, particularly certain Japanese breeds like Akitas and Shiba Inus. The oxidants bind directly to the erythrocytes, so these dog breeds are particularly at risk because of the specific chemical make-up of their red blood cells. All dogs are susceptible however, in contrast to humans whose red blood cells aren’t affected by the organosulfoxides. As the oxidant level within erythrocytes become higher than the cells’ antioxidant metabolism capacity, a condition called oxidative hemolysis results which affects oxygen transport and causes red blood cells to rupture and be destroyed. The erythrocytes will be marked by Heinz body formation, an abnormal blood cell visible upon microscopic examination of a blood smear. Dogs with allium species toxicosis develop hemolytic anemia. Typically the onset is delayed by several days, but large doses may cause symptoms of anemia as little as one day after ingestion. Vomiting, diarrhea and gastrointestinal upset may also be present. The toxic dose is typically 15-30 grams per kilogram of the dog’s weight, or about .5% of the body weight. All types of allium species can cause this toxicity, but garlic is the most concentrated and therefore the most dangerous for dogs. Dried, powdered, and cooked products are just as toxic as those that are fresh and raw. As the condition progresses, the bone marrow will generate new red blood cells and the anemia will pass, as long as no further exposure takes place. High doses might need to be treated with a blood transfusion to avoid fatally low levels of erythrocytes.Onions, garlic and other members of the allium family can be toxic to dogs. This is called allium species toxicosis, or onion toxicity. Signs may take several days to manifest.Youtube PlayOnion Poisoning Average CostFrom 61 quotes ranging from $500 - $3,000Average Cost$950Protect yourself and your pet. Compare top pet insurance plans.

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Symptoms of Onion Poisoning in DogsThese signs could indicate your dog has eaten onions or garlic.

• Smell of onions or garlic on the breath
• Excessive salivation
• Irritation of the mouth
• Vomiting
• Diarrhea
• Lethargy
• Signs of abdominal pain
• Rapid heartrate (tachycardia)
• Panting (tachypnea)
• Weakness
• Exercise intolerance
• Collapse
• Pale or bluish gums

Types These are the types of products you should keep away from your dog.

• Garlic – most toxic, about five times as potent as onions
• Onions
• Leeks
• Chives
• Scallions or green onions
• Garlic or onion powder

Causes of Onion Poisoning in DogsThese are some of the causes and risk factors associated with allium species toxicity.

• Ingestion of fresh growing onions, garlic or chives
• Feeding food prepared for humans to a dog
• Dog chews open a container of dried or powdered onions or garlic
• Certain breeds are more susceptible (Japanese breeds like Akita and Shiba Inu)
• Some factors can make the red blood cells weaker and increase a dog’s susceptibility to allium species toxicosis (Zinc deficiency, glucose-6-phosphate dehydrogenase which is an inherited deficiency, and some drug treatments

Diagnosis of Onion Poisoning in DogsIf you know your dog has ingested a product that contains onions or garlic this will make diagnosis easier. If the dog is already showing signs of lethargy and weakness, indicators of hemolytic anemia will likely be visible on a blood test. This can also help to indicate the severity of the problem. Urinalysis may show high levels of hemoglobin in the urine. Heinz body anemia may be visible on a blood smear examination even before there is a marked drop in red blood cells. Other signs, like a smell of onions or garlic on the breath (with recent ingestion), or vomiting and diarrhea with undigested pieces may also be an early indication that your dog has allium species toxicosis. For unknown instances of poisoning, the veterinarian may ask what foods you regularly give your dog and suggest you check the list of ingredients.Treatment of Onion Poisoning in DogsIf the poisoning is still recent, vomiting may be induced and the dog may be given activated charcoal to reduce absorption in the gastrointestinal tract. The veterinarian will tell you to monitor your dog for signs of anemia over the next few days and may recommend a diet low in oxidants. If a large amount has been ingested, your dog may need to be kept in a veterinary hospital for that time period. Severely ill dogs will likely need supplemental oxygen to make up for the reduced circulation of red blood cells and a blood transfusion could be necessary to stabilize your dog until the bone marrow is able to generate enough new, healthy erythrocytes.

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Recovery of Onion Poisoning in DogsDogs will likely recover from mild exposure to onions or garlic, but severe poisoning can be fatal, especially without treatment. If you know you dog has eaten an excessive amount of onions or garlic, you should take him to the veterinarian immediately even if there are no immediate signs.  Avoiding exposure is the best way of managing the condition. If you are feeding your dog any food prepared for humans, check the list of ingredients for onions, garlic or other allium products. Even if your dog remains asymptomatic, continual low level doses will make any accidental ingestion much more serious. Put any spoiled food that contains onion or garlic products through a garbage disposal or place in a sealed trashcan. Take precautions if there are allium species growing in your garden. Dogs don’t normally like the taste of these plants, but it’s safer to keep them out of reach.Onion poisoning can be expensive to treat. If you suspect your dog has onion poisoning or is at risk, start searching for pet insurance today. Brought to you by Pet Insurer, Wag! Wellness lets pet parents compare insurance plans from leading companies like PetPlan and Trupanion. Find the “pawfect” plan for your pet in just a few clicks!Paying for your pet’s routine shots, bloodwork and tests can be also difficult to budget for. Fortunately, Wag! Wellness plans cover costs for routine care for your pet, getting your money straight back into your bank account within 24 hours. In the market for wellness plans? Compare wellness plan packages to find the right plan for your pet!Onion Poisoning Average CostFrom 61 quotes ranging from $500 - $3,000Average Cost$950Protect yourself and your pet. Compare top pet insurance plans.TopOnion Poisoning Questions and Advice from Veterinary ProfessionalsDachshundOne Year

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74 found this helpful

My pet has the following symptoms:My dog ate some ham that had been cooked with onion. I don’t think she ate any actual pieces of onion but I’m worried. She doesn’t have any symptoms.Sept. 19, 2021Answered by Dr. Sara O. DVM74 RecommendationsHello if she ate any onion she may vomit or have diarrhea. If you notice anything off I would recommend a vet visitSept. 19, 2021Was this question and answer helpful?

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PomeranianFifteen Years

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My pet has the following symptoms:Lethargy, Shaking, Back Legs Weak (Never Were Before 2 Days Ago)My 15 year old dog has heart issues but otherwise in decent health. She ate a White Castle hamburger with onions. A week later after the onion, her back legs are very weak and she is shaky. Could it be onion related?Feb. 1, 2021Answered by Dr. Maureen M. DVM52 RecommendationsHi, It's highly unlikely that the onions are causing the symptoms you are observing. Hind limb weakness could be caused by various factors such as neurological conditions, arthritis, hip dysplasia, tick-borne infections among others. Please visit your vet for a thorough check-up and a more confirmatory diagnosis. Good luckFeb. 2, 2021Was this question and answer helpful?

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