Two Easy Ways to Start Earning Rewards!
Become a member today!
Members-only pricing and offers, personalized care notifications, Vital Care points back on every purchase and more!
Already a member? Sign in
Become a credit card member today!
Earn 2X Pals Rewards points at Petco
when you use Petco Pay!
APPLY NOW
Learn More About Petco Pay Benefits

My cat ate Subway tuna salad with onion. Is it safe for her?

Updated on September 23rd, 2025

Pet's info: Cat | American Shorthair | Female | spayed | 12 years old

Will my cat be okay after eating a few bites of tuna from Subway? I fell asleep after almost finishing a tuna salad (made with mayo I assume) sandwich from subway. A bunch of veggies on it including onion, and black pepper and chipotle sauce. When I woke the tuna had been licked out. I think most of the veggies were eaten by me before I fell asleep. Could have been any time between 6 hours ago & now. My cat is 12 years old and has asthma. I am with her now and she seems totally fine.

3 Answers

Most Helpful Answer

Answered By Jennifer Summerfield, DVM CPDT-KA

Veterinarian, Certified Dog Trainer

Published on January 8th, 2017

The tuna salad itself should not cause any serious problems at all. The only thing on your list that is potentially toxic to cats is onion - so you think she may have eaten a significant amount of onion, it would be best to take her to the vet to be safe. Otherwise, I would not expect her to have any serious issues. You may see some mild stomach upset for the next day or so, if she isn't used to eating human food like this, but no toxicity concerns.

11Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Maria DVM
Veterinarian
Published on July 29th, 2018
I do recommend taking Chandler to your veterinarian. It is great that he vomited some onions up but my concern is there can be more. Here is some information on onion toxicity in pets:
https://phz8.petinsurance.com/pet-health/pet-toxins/pets-and-onions
Thank you for using PetCoach.
1Pet Parents found this answer helpful
Answered By Laura Johnson VMD
Veterinarian
Published on April 16th, 2018
Hi, thanks for using Petco Pet Education Center, formerly Petcoach!

It is hard to guide you since you do not know if or how much onion there was in the tuna. I can tell you that most of the time the pets are fine. If she is acting fine then I wouldn't rush to the ER. Onion toxicity isn't immediate and it usually is when they eat a lot of there is chronic exposure. I think you can wait for your Vet to open and if you are still nervous have her examined and some blood work done.

Have a great day!
1Pet Parents found this answer helpful

Smart Picks for Smart Questions

Related Questions

Health & Wellness

My cat ate lemon pepper tuna. Is it safe? What symptoms to watch?

Onion or garlic would be the main seasonings that I can think of that would be toxic in something like this, and I doubt there would be anywhere near enough present to cause a problem. If you can repost your question with a picture of the ingredients we can confirm that there is nothing else that would cause toxicity.

Updated on September 23rd, 2025

Training & Behavior

My cat licked caramelized onion. Is it safe for my cat to eat?

Hello, I'm sorry to hear that Luna got into the pan with onions. Generally, she would need to eat a few mouthfuls of pure onion to get a toxic amount. A few licks of oil in a pan with onion in it wouldn't cause problems, except maybe some GI distress from excess fat. If she did ingest a toxic amount of onions, it would cause anemia which results in weakness and lethargy. If you are concerned about the amount she ingested, call her veterinarian and schedule an appointment for a physical exam and bloodwork. I hope this helps. Thanks for using Petco Pet Education Center, formerly Petcoach.

Updated on September 23rd, 2025

My cat ate fish with ketchup & onion powder. Will he be okay?

The very small amount of onion powder in this shouldn't cause your cat any problems. He may get some stomach upset due to getting a decent amount of unfamiliar food, but no more than that. If he should become ill, refuse to eat, etc, get him in to see your vet right away.

Updated on September 23rd, 2025

Health & Wellness

My cat ate salmon with garlic. Is it safe or toxic for cats?

It is likely Steve did not ingest a toxic dose. Monitor for lethargy, pale gums, difficulty breathing or exercise intolerance for the next 24-72 hours. You may see some minor stomach upset which, in the absence of other symptoms, can be managed with a short fast followed by a bland diet fed in small, frequent amounts until symptoms resolve. If he develops any of the other symptoms, have him seem by your veterinarian.

Updated on September 23rd, 2025

Dog ate tuna sandwich with onion and garlic. Will he be okay?

Dixie will probably be just fine. It takes quite a bit of onion and garlic to cause clinical signs of toxicity - for a 40 lb dog the toxic dose would be 20 grams of onion or 5 grams of garlic. Both onion and garlic cause destruction of red blood cells leading to anemia. Onion and garlic powder can be more concentrated than the raw vegetables and therefore more likely to cause a problem, but I doubt there would be enough of either in a tuna sandwich. We also tend to see more problems when small amounts are given frequently rather than a single one time exposure.

Updated on September 23rd, 2025

Food & Nutrition

Is it safe to give my cat tuna or sardines as a food substitute?

If your cats have not had any issues with either product then they are probably ok for a treat occasionally for your kitties. The sardines if they contain bones may pose a slight risk as occasionally we can see obstruction or damage to the esophagus or stomach due to bones. If the sardines in tomato sauce have garlic or onion in them, they would not be recommended. Neither food would be recommended as a sole diet however as they wouldn't be a complete and balanced diet for your kitty.

Updated on September 23rd, 2025

Food & Nutrition

Is it safe if my 4-month-old kitten ate pepperoni from pizza?

There is no concern for toxicity here. Pepperoni may cause some upset stomach issues but other than that she should be fine. If you do see some upset stomach symptoms (vomiting, diarrhea), then you can try a probiotic (i.e. Culturelle over the counter) and a bland diet of lean ground beef and rice and pumpkin (not the pie filling) for a few days, then slowly transition her back to her normal diet. I hope that your fur baby Tor turns out well with no upset stomach. Take care!

Updated on September 23rd, 2025

Have A Vet Question?

Book an appointment with the pros – our expert vets are here to help.

Share