Anna Olson

Anna has a passion for keeping pets healthy and happy. She grew up with a Great Pyrenees as a family dog. Currently and currently has an orange tabby. She worked at a dog grooming and bathing salon where she learnt more about canine behavior and bathing. She lives in Wisconsin, in the United States. When she is not writing, she helps her partner run their small business, knitting, and enjoying local parks.


Fish Oil For Dogs: The Complete Guide

Anna Olson
Sep 4 ·

You may have heard about the medical benefits of fish oil, both for you and for your dog. Your vet or pet nutritionist may have recommended it for your dog’s arthritis or dry skin. At the same time, you want to make sure this popular supplement is the right choice for your pup before giving it to them. With our Fish Oil for Dogs: The Complete Guide, you’ll get a better idea of whether fish oil capsules or liquid would be beneficial for your pup.

fish oil for dogs the complete guide

What’s In Fish Oil?

The main beneficial ingredient in fish oil, both for humans and for dogs, are omega-3 fatty acids. These are an essential nutrient, one that dogs can’t produce on their own. These fatty acids are found in cold-water fish, shellfish, plant and nut oils, and flaxseed. Cold-water, short-lived fish, like salmon, are the best source of omega-3 fatty acids for dogs.

Omega-3 fatty acids are necessary for life-long health of your dog. In puppy stages, they help the development of your dog’s eyes and brain. In old age, it can also help your dog’s cognitive function, and help relieve some of the pain of arthritis. Most importantly, omega-3 fatty acids help balance buildup of more processed omega-6 fatty acids. If your dog is eating processed food from meat animals fed processed corn or grains, it’s likely they have too much omega-6 buildup.

Even though fish oil contains necessary nutrients, it’s important to talk to your vet before starting your dog on this new supplement.

Talk With Your Vet

Before you start feeding your dog fish oil, call your veterinarian, or consult with a certified pet nutritionist. This goes for any new food or supplement, too. Your vet should know your dog, their sensitivities, and any medication or supplement they might be taking. They’ll also be able to determine what type and amount of supplement would best suit your dog’s breed, size, and weight.

Your vet may prescribe fish oil either for short-term or long-term use. In the U.S., supplements are not as regulated by the FDA as other medications. Make sure to follow your vet’s instructions for administering a fish oil supplement. Their instructions may differ from those on the packaging.

Corgi and woman

Weighing The Pros and Cons of Fish Oil

Fish oil has many reported health benefits. However, it can also interact negatively with other medications and supplements. Long-term consumption has been linked to certain health issues in some dogs. Sometimes, it can also cause side effects. This makes it extra important to talk to your vet about fish oil before giving it as a supplement. Below are benefits, downsides, and side effects of supplemental fish oil.

Potential Benefits

Since fish oil supplements have been the subject of a lot of scientific research and studies, you can rest assured most of these health claims are well-supported. These health claims include:

  • Heart health support
  • Coat and skin health
  • Allergy relief
  • Joint pain relief
  • Natural anti-inflammatory agent
  • Strengthen your dog’s immune system
  • Cancer-fighting

Potential Downsides

Even though fish oil could have a lot of benefits for your pup, there are some risks and downsides, especially if your dog takes it long-term.

There are a few dogs for whom fish oil should only be given with caution, if at all. These include dogs with diabetes, diarrhea, and pancreatitis. Since fish oil interacts negatively with anti-coagulant medication, and can act as a blood thinner, use it with caution if your dog is taking an anti-coagulant or has a blood clotting disorder. Use fish oil with caution if your dog is pregnant or nursing. Your vet should be able to help you figure out a beneficial dosage, no matter what your dog is going through.

If you live in the United States, you may know that supplements don’t get much oversight from the FDA. Be careful with what you buy. Your veterinarian should be able to recommend a brand or type that’s best for your dog.

If your dog takes fish oil long-term, they risk developing a vitamin E deficiency. This means your vet will have to prescribe a vitamin E supplement, too. Symptoms of vitamin E deficiency in dogs include muscle weakness and decreased fertility.

Heavy metal toxicity is another risk of taking fish oil long-term. This can have many frightening symptoms, including abdominal issues, seizures, blindness, and running around aimlessly. If you see any of these symptoms, stop giving your dog fish oil and contact your vet immediately.

Negative Side Effects of Fish Oil

Side effects of fish oil consumption include:

  • Diarrhea
  • Vomiting
  • Delayed wound healing
  • Drowsiness
  • Fishy odor in breath or skin
  • Increased itchiness
  • Oily skin
  • Skin flaking

Usually these side effects resolve on their own after you stop giving your dog fish oil.

How To Buy and Keep Fish Oil

While most fish oil supplements are sold in capsules, a few for dogs are sold in liquid form. While your dog can easily be trained to take capsules every day, you may lean more towards the liquid type. It’s easier to mix into your dog’s food. Both offer the same potential benefits.

There are currently three types of fish oil sold on the market. While natural triglyceride oil is the easiest to absorb, it has a higher likelihood of having other contaminants. Synthetic triglyceride oil is the least likely to have contaminants, but is also the hardest for the body to absorb. Ethyl ester oil contains both natural and synthetic ingredients, and can be considered in between natural and synthetic triglyceride oil in terms of ease of absorption and likelihood of contaminants.

Once you’ve selected your dog’s fish oil, make sure to protect it from light, air and heat. Since fish oil oxidizes quickly, buy it in dark bottles and keep it in your fridge. Smell it frequently. If it has a rancid or off smell, throw it away and buy new fish oil.

Fish Oil Dosage

Your vet or a certified pet nutritionist will be able to determine the right dosage amount for your dog and offer a dosage schedule. It’s very important to follow a schedule when giving your pup fish oil. Don’t give your dog extra doses at once. If you miss a dose, just offer the next one on its own.

Using our Fish Oil For Dogs: The Complete Guide, you hopefully have a better idea of whether fish oil would be right for your dog. It’s important to discuss any new supplement with your vet, or certified pet nutritionist. It’s also important to follow their dosage instructions and recommendations.

Why Does My Dog Smell Like Fish?

Anna Olson

Anna has a passion for keeping pets healthy and happy. She grew up with a Great Pyrenees as a family dog. Currently and currently has an orange tabby. She worked at a dog grooming and bathing salon where she learnt more about canine behavior and bathing. She lives in Wisconsin, in the United States. When she is not writing, she helps her partner run their small business, knitting, and enjoying local parks.

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