Onion Toxicity Average Cost

From 288 quotes ranging from $500 - 4,000

Average Cost

$2,000

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What is Onion Toxicity?

Onion toxicity results in hemolysis, or the breakdown of red blood cells. As the cells break down, the feline has less cell circulating in the body, creating signs of weakness and panting due to the fact that these cells carry oxygen. Onion toxicity can be fatal in cats if immediate veterinary care is not sought.

Onion toxicity in cats is a hypersensitive reaction of the feline’s red blood cells to the oxidant present in fresh or dried onions. An onion can become toxic to a feline if more than 1 gram per 5 pounds of body weight is ingested. Onion powder has a high toxicity rate and is potentially more potent than a fresh onion. The toxic agent present in onions is caused by the oxidant n-propyl disulfide. 

Symptoms of Onion Toxicity in Cats

The symptoms associated with onion toxicity in cats are paired with those found in an allergic reaction caused by an ingested agent. Common clinical signs noted after a feline has ingested onion includes: 

  • Panting 
  • Elevated heart rate 
  • Weakness 
  • Hematuria (blood in the urine) 
  • Hemolytic anemia (breakdown of red blood cells)
  • Heinz body anemia (breakdown of red blood cells)
  • Vomiting 
  • Gastrointestinal upset 
  • Asthmatic attacks 
  • Allergic reaction 
  • Liver damage 
  • Diarrhea 
  • Decreased appetite 
  • Lethargy 
  • Contact dermatitis (skin exposure) 
  • Fainting 

Causes of Onion Toxicity in Cats

An onion can become toxic to a feline if more than 1 gram per 5 pounds of body weight is ingested. Onion powder has a high toxicity rate and is potentially more potent than a fresh onion. 

Onion toxicity in cats is caused by the oxidant present in onions, n-propyl disulfide. Cats have a high sensitivity for red blood cell oxidation, due to the larger surface area for oxidizing agents to attach to the cell. When the oxidant, n-propyl disulfide is digested and enters the bloodstream, the body interprets this irregular oxidant as a foreign invader. As the oxidant has already attached to the red blood cell and cannot readily be removed, the body destroys the cells in an attempt to remove the harmful substance. The end result is hemolysis, or the breakdown of red blood cells. 

Diagnosis of Onion Toxicity in Cats

The veterinarian will begins the diagnostic process with a physical examination and a review of your cat’s medical history. He or she will ask you cat’s current diet, including table scraps or ingredients in her raw food diet. 

Onion toxicity in cats is commonly diagnosed through the examination of a cat’s red blood cells. As hemolytic anemia is a common clinical sign of onion toxicity, the present of Heinz bodies on the edge of a red blood cell, seen microscopically, will indicate oxidative injury. The diagnostic tool to reveal this clinical sign is called a blood smear, requiring only a small sample of blood from the feline. 

Hemolytic anemia is also a clinical sign of several other common feline diseases, so your veterinarian will likely request a biochemistry profile or radiographs to complete the differential diagnosis.

Treatment of Onion Toxicity in Cats

No specific antidote is available for onion toxicity and the condition is mainly treated with supportive care. The feline may be hospitalized and administered intravenous fluid therapy. The fluid therapy is used to flush the body of the toxin and give the body time to stop hemolyzing its red blood cells. In most cases, once the ingestion of the toxin has ceased, the cat’s bone marrow will begin creating new, healthy red blood cells to replace the previously destroyed cells. In severe blood loss cases, the feline may require a blood transfusion to replenish the body’s blood supply.

Recovery of Onion Toxicity in Cats

Improvement following treatment of onion toxicity will be seen within hours to a day, depending on the cat’s toxic state. Once the feline is stable, the veterinarian may choose to run additional lab work including examination of the blood and urine to ensure the body’s organs are functioning at full capacity. Follow-up appointments are not necessarily required, but the veterinarian may choose to have your cat reevaluated if a blood transfusion was required in the treatment process. 

To avoid onion toxicity in cats, pet owners should avoid feeding table scraps and baby food to the feline. Cats do not usually eat onion by itself, but mixed into a food, it can easily be ingested. Always keep fresh onions, onion powders, onion salts and other products containing onion out of your cat’s reach.

Onion Toxicity Questions and Advice from Veterinary Professionals

Juno
Dark Tortoiseshell
5 Years
Fair condition
0 found helpful
Fair condition

Has Symptoms

None yet

My cat licked a piece of onion about 45 minutes ago when I pulled it off a slice of pizza. She began grooming shortly afterwards and I googled if they were toxic or not. When I learned they were I got her to drink some water (within about 10 minutes of ingestion) and she behaved normally afterwards. She was playful and active, and after about 15 minutes I fed her at her normal dinner time, 5pm. She ate normally and is behaving normally now, at 5:20pm. When should I bring her to the vet? When will I be able to tell if she was affected by the onion? She really didn’t seem to ingest hardly any at all, it was literally a single small lick. But I want a professional opinion on whether or not I should take her to the vet, and how soon it needs to be. I could take her to her usual vet that I trust in the morning, but if she needs a vet tonight I’ll take her anywhere I can.

Dr. Callum Turner, DVM
1679 Recommendations
A lick of an onion (not actually consuming any pieces) shouldn’t cause any trouble, the problem comes when a cat (or dog) consumed some onion as the Allium in the onion is toxic for their red blood cells and causes anaemia; I would keep an eye on things for the time being and if she starts being lethargic, has pale gums or any other symptom (may take a few days) listed on this page you should visit your Veterinarian. Regards Dr Callum Turner DVM

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Harley
American Shorthair
7 Months
Fair condition
0 found helpful
Fair condition

Cat may have stolen a tiny piece of fried onion off my plate. I couldn't say for sure as I didn't see her take it but she was chewing when I looked at her. She is not showing any of the above visible symptoms but am monitoring her. Still has a healthy appetite. Should I be worried? How do I know she's in the clear? She is about 6 lbs

Dr. Callum Turner, DVM
1679 Recommendations
A tiny piece of onion may not cause any symptoms, but generally the serious symptoms of onion poisoning takes a few days to present with anaemia so you would notice the gums going pale. Keep a close eye on Harley and visit your Veterinarian if you have any concerns. Regards Dr Callum Turner DVM

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Toby
DOMESTIC
10 Weeks
Mild condition
0 found helpful
Mild condition

Has Symptoms

Nothing yet except a lot of licking

My kitty stepped in my egg salad that had onions! He got some of the Mayo onion on his paw and tail. Can this be toxic? I immediately wiped down his foot and tail with cat wipes

Dr. Callum Turner, DVM
1679 Recommendations
If there was no ingestion of the egg salad, Toby should be fine; onion poisoning doesn’t go through the skin, not that efficiently anyway. Just make sure that the egg salad is thoroughly cleaned off and if any was consumed induce vomiting with 3% hydrogen peroxide. Regards Dr Callum Turner DVM

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Beau
American Shorthair
13 Years
Fair condition
0 found helpful
Fair condition

Medication Used

prednisone

Beau ate 2 tablespoons of a sour cream based caramelized onion dip does he need to go to the vet?

He is behaving normally, does not clear to be nausious.

He has ibd/lymphoma and is on prednisone, probiotics, cerenia as needed

Dr. Callum Turner, DVM
1679 Recommendations
Symptoms of onion poisoning isn’t immediate but may cause some gastrointestinal symptoms as well as haemolytic anaemia in some cases; inducing vomiting is best but may not be wise with his current treatment. Also, other ingredients in the dip may be dangerous for dogs too so check that out; if in doubt visit your Veterinarian. Regards Dr Callum Turner DVM

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