Fish Allergies in Dogs: Symptoms & What to Do!

by Sarah Seward-Langdon on November 23, 2022

Fish Allergies in Dogs: Symptoms & What to Do!

Written by: Sarah Seward-Langdon

Published on: 11/22/2022

Looking through all of the dog food brands out there, you’re probably familiar with fish being a common ingredient for your furry friend. Heck, it’s probably a common staple for us humans in most households as well. Not only does fish taste great, but it also provides both us and our dogs with great benefits. So, what do you do if you think your dog has fish allergies?!

Fish allergies in dogs aren’t very common, especially when comparing the number of dogs that suffer from allergies (or sensitivity) to proteins like chicken or beef. However, if you think your dog may have allergies to fish, then you may need to find substitutes to add to your dog’s diet.

This article will explore why fish is beneficial to dogs, how to spot allergies or intolerances to fish, and what to do in this situation. Allergies may be common in dogs these days, but they are very easily manageable and not something to worry about if you get them under control.

Benefits of Feeding Fish to Your Dog

Why feed your dog fish when they have so many other options out there?

Fish is obviously a great source of protein, but it’s more famously known as one of the main natural sources of essential fatty acids (EFAs) for dogs. Essential fatty acids, one of them being omega 3s, may help a dog’s skin and coat, digestion, and immune system. Many people also use it to help their pup’s combat joint pain and inflammation [1]!

Not only does it provide EFAs, but it also gives dogs important minerals for their health, including zinc, magnesium, potassium and many more [1].

Aside from health benefits, it can also be helpful for dogs who are picky eaters. Since it has a strong smell and taste, some dogs find it to be more palatable. Even if your dog isn’t getting chunks of fresh fish in their meal, some owners swear by adding fish oil to meal times, which helps their fussy pet enjoy their food.

What Are Fish Allergies?

Fish allergies are like any other allergy; they are your dog’s body reacting badly to a specific allergen, whether it be food or environmental.

When it comes to food allergies, antibodies in your dog’s body are produced that react to a specific ingredient, or ingredients, of their diet. These antibodies identify the food allergen as a threat even though it isn’t, and your dog’s immune system reacts to try and protect them from harm [2].

Something interesting to consider is that food allergies often develop over time, after your dog has been exposed to the allergen for longer periods. This is because antibodies need to be exposed to the food for an allergy to develop [2].

What does this mean? Your dog could be happily eating high-quality chicken-based kibble for many years, and start showing allergy symptoms later. These symptoms could imply that your dog has developed a sensitivity to chicken since they were eating the same food for so long.

Symptoms of Fish Allergies

Not sure if your precious pup is suffering from allergies? Here are a few of the main symptoms you should watch out for [2]:

  • Itchy and inflamed skin
  • Upset stomach
  • Vomiting
  • Diarrhea

Those are the most obvious symptoms and if your dog starts showing any of these, we recommend you take them to a vet to properly discover the cause. Other more subtle allergy symptoms can sometimes include: hyperactivity, weight loss, and lack of energy. In extremely rare cases, some dogs will even exhibit aggression [2]!

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How to Diagnose: Elimination Diet

But wait—it may not actually be a fish allergy! So, before sentencing your dog to a lifetime without fish, make sure that you confirm they do indeed have a fish allergy.

To identify what your dog is allergic to, you can go to your vet and ask for an allergy panel; however, these tests can sometimes be unreliable. One of the most talked about ways to identify what bothers your dog is practicing an elimination diet.

Most people get a bit scared when they hear about an elimination diet; however, if you work with your vet and break down the steps, it’s not as daunting as you may have initially thought. Although we can’t help you with the vet part, here’s a simple breakdown of the possible process that you would go through with your vet [3]!

Step 1: Talk to Your Vet

Before you start an elimination diet, we suggest speaking with your vet! Even if you’ve done it before, your vet can give you new insight. They’ll be helpful in making sure you’re doing the elimination trial correctly and can analyze your findings properly!

Step 2: Start Feeding a Specific Diet

Once you’ve spoken to your vet about your pet’s symptoms and how to proceed, you’ll need to switch your dog to a prescribed home-cooked diet or a prescription diet. Whichever diet is chosen, it will need to be made with a novel protein and carbohydrate source—in other words, food that your dog has not been exposed to and therefore won’t likely be allergic to.

Be careful with the food you decide on, because if you want to try and just switch your pet to a limited-ingredient food from the pet store, the elimination trial may not work. This is because many commercial pet store food brands have hidden ingredients or are just not as pure as the alternatives mentioned before.

Step 3: Be Strict for At Least 12 Weeks

This elimination diet needs to be strictly followed for at least 12 weeks minimum. It could be more, because it also needs to be followed until at least a month after any skin infection is resolved.

You cannot feed your pet extra treats (that aren’t discussed to be included in the elimination diet) or table scraps. They can’t have chews or even treats that you use to feed them their medication. Remember, this is a strict trial!

Step 4: Analyze Results

During this entire process, you should be monitoring your pet and checking in with your vet. If your dog truly has a food allergy, they will hopefully see a reduction of some of the more common allergy symptoms by around 50%.

Step 5: Diet Challenge

This is the step you can do if you’re trying to find out what they are specifically allergic to. Re-introduce an ingredient that you think is a culprit. If your dog is in fact allergic, they will likely exhibit symptoms in as little as a few hours or within a few days.

You can keep adding in different ingredients as you test. This is a good way to identify specific allergies and if your dog is allergic to more than one ingredient!

Feeding Your Dog with Fish Allergies

So you’ve figured out your dog has fish allergies. What are your options?

Alternative Proteins & Types of Pet Food

Try feeding your dog novelty proteins. They may be more expensive, but you’ll probably spend less time at the vet (and therefore less money) and have a happier dog!

Novel proteins are harder to find and are often more expensive. But they are gradually becoming more accessible to pet parents. You can find things like venison, kangaroo, rabbit and sometimes even camel in the pet stores these days.

If you’re looking for another way to change up your dog’s diet, consider talking to your vet about switching the type of food your dog eats. This could mean switching your dog from kibble to homemade food, raw meals, a mix, a veterinarian diet, etc.—there’s so many options out there and you just need to find what is best for your dog.


As mentioned before, one of the main benefits of consuming fish for dogs is that it’s a natural source of omega 3 fatty acids. To ensure their dog is reaping all the benefits, many owners add fish oil to their diet. However, if your dog is allergic to fish, that isn’t a feasible option for your dog.

Instead, you can look towards plant-based oils to make sure your pet gets the omega 3s he or she needs to thrive! The most common ones out there are flax and hemp oils. One that is more uncommon and newer to the pet scene is camelina oil.

Camelina oil is a great omega 3 supplement as it’s easily digestible, affordable, and gentle on the environment! It is also more self-stable than other plant-based omega supplements so that you don’t need to worry about it going bad.

Camelina Oil for Equine

✅ Single ingredient, 100% pure Camelina Oil.
✅ Non-GMO
✅ Ideal balance of Omega-3 compared to other products, like soybean oil.
✅ Canadian produced and operated.

Camelina Oil for Canine


✅ Single ingredient, 100% pure Camelina Oil.
✅ Non-GMO
✅ Ideal balance of Omega-3 compared to other products, like soybean oil.
✅ Canadian produced and operated.

Say Goodbye to Your Dog’s Allergy Symptoms

Now you are equipped with knowledge on dog allergies, especially dog allergies to fish! Whether you’re still in the process of confirming an allergy diagnosis, or you’re trying to find ways to support your dog with confirmed allergies, there are options out there for you.

We know it’s stressful to see your dog uncomfortable, so we hope that you’re able to take away some actionable information from this piece. As always, the vet is your friend so take all the information you’ve researched and work together with a trusted professional to make a plan that’s suitable for your unique dog.

Good luck! We’re rooting for you.



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About Sarah

Sarah is a marketing specialist with a passion for anything creative! Her openness to working across industries and job opportunities has allowed her to gain enormous amounts of experience in graphic design, video production, and written content creation. Animals have a special place in her heart as she grew up with cats and now owns her own Alaskan Malamute. She has spent the last couple of years in Vancouver working with different companies within the pet industry and gained valuable knowledge about the ins and outs of the (alternative) pet food industry, supplementation, and various training methods. When she’s not digitally creating content for pet lovers to consume, she’s out eating great food, dancing at drop-in classes, or exploring the beautiful Canadian scenery with her fur-child Miso.