How Much Fish Oil Can I Give My Dog? EPA and DHA Dosage by Body Weight in Canada

Most dogs do well on roughly 50 to 75 mg of combined EPA and DHA per kilogram of body weight per day for skin and joint support — about 500 to 750 mg daily for a 10 kg dog. Keep the total under the widely cited safe upper limit of 370 mg per kg of metabolic body weight, and confirm the dose with your veterinarian first.

That single number — combined EPA plus DHA, not "fish oil" — is where almost every dosing mistake starts. A 1,000 mg softgel usually delivers only about 300 mg of actual omega-3s, so the label weight and the useful dose are rarely the same thing. If you're already comparing bottles, our dog health and wellness collection lists the guaranteed analysis for each supplement so you can do the math before you buy.

What the standards say about omega-3s for dogs

AAFCO sets a minimum of 0.05% combined EPA and DHA on a dry-matter basis for dog foods labelled for growth and reproduction, alongside 0.08% alpha-linolenic acid, with no equivalent minimum for adult maintenance diets. That means an adult kibble can legally contain almost no marine omega-3 at all — which is precisely why supplementation is a conversation worth having.

The AAFCO dog food nutrient profiles, carried forward unchanged into recent Official Publications including 2026, also cap the omega-6 to omega-3 ratio at 30:1. Most grain-inclusive and grain-free kibbles land somewhere between 10:1 and 20:1 because chicken fat, poultry meal, and vegetable oils are rich in linoleic acid. Adding EPA and DHA pulls that ratio down toward the range associated with lower inflammatory signalling.

Where does the ceiling come from? The National Research Council's safe upper limit for dogs is 370 mg of combined EPA and DHA per kilogram of metabolic body weight (body weight in kg raised to the 0.75 power) per day. Practically, that's around 2,080 mg for a 10 kg dog and about 5,880 mg for a 40 kg dog. Doses above that have been linked in veterinary literature to platelet dysfunction and delayed wound healing. Peer-reviewed omega-3 trials in dogs — many of them indexed on PubMed, with reviews published through 2024 — cluster their osteoarthritis dosing between 50 and 100 mg/kg body weight daily.

EPA and DHA dosage by dog body weight

Here's the general skin-and-joint support range (50–75 mg/kg combined EPA+DHA daily) alongside the NRC safe ceiling:

• 5 kg / 11 lb — roughly 250–375 mg EPA+DHA daily; upper limit near 1,235 mg
• 10 kg / 22 lb — roughly 500–750 mg daily; upper limit near 2,080 mg
• 20 kg / 44 lb — roughly 1,000–1,500 mg daily; upper limit near 3,500 mg
• 30 kg / 66 lb — roughly 1,500–2,250 mg daily; upper limit near 4,740 mg
• 40 kg / 88 lb — roughly 2,000–3,000 mg daily; upper limit near 5,880 mg

Two housekeeping notes. First, calories count: a teaspoon (5 ml) of fish oil carries about 40–45 kcal, so a large dog on 2 teaspoons a day is eating an extra 80–90 kcal — enough to matter for a dog already carrying weight. Second, the Canadian Veterinary Medical Association and AVMA both stress that supplements should be discussed with your vet, especially for dogs on anticoagulants, dogs with a history of pancreatitis, or dogs scheduled for surgery.

What we see in the store when owners ask about fish oil

The single most common error we correct at the counter is dosing by capsule count instead of by EPA+DHA content. Pet owners tell us they're giving "two fish oil pills a day" to a 35 kg shepherd — that's often only 600 mg of actual omega-3s, well under half of what the research range suggests for a dog that size.

Our nutrition experts at the North York store walk through the same three checks every time. We read the guaranteed analysis or supplement facts panel for milligrams of EPA and DHA per pump, scoop, or capsule. We check whether vitamin E (mixed tocopherols) is included as an antioxidant, since fish oil oxidizes quickly once opened. And we ask what the dog is already eating — a dog on a salmon-forward diet from our raw dog food selection or an air-dried formula with whole fish already gets a meaningful baseline.

The seasonal pattern is hard to miss. From November through March, when GTA condos and townhomes run dry forced-air heat, we see a wave of owners describing flaky skin, dull coats, and dogs scratching at the base of the tail after a walk through Downsview Park. Fish oil isn't a fix for every itch — allergies, fleas, and yeast all look similar from the outside — but omega-3s are one of the few interventions with consistent evidence behind coat quality and inflammatory skin comfort.

When a customer comes in asking about an arthritic senior, we typically suggest pairing EPA and DHA with a joint formula containing glucosamine rather than treating fish oil as a standalone answer. You'll find us at 1111A Finch Ave W, Unit 2, North York, ON M3J 2P7 (open 7 AM to 11 PM daily); most GTA addresses can get same-day delivery through SkipTheDishes or a similar app.

Fish oil for dogs: your questions answered

Can I give my dog human fish oil capsules?

Yes, plain human fish oil softgels are generally acceptable for dogs provided they contain only fish oil and vitamin E, with no xylitol, flavourings, or added herbs. A standard 1,000 mg capsule supplies roughly 180 mg EPA and 120 mg DHA — about 300 mg combined. Avoid cod liver oil, which carries high vitamin A.

That vitamin A caution is worth repeating. Cod liver oil can contain 1,000–1,500 IU of vitamin A per teaspoon, and chronic oversupply is associated with skeletal problems. If you want the omega-3s without the retinol load, choose a body-oil product (sardine, anchovy, salmon, or mackerel) rather than a liver oil.

How long does fish oil take to help an itchy dog?

Expect 6 to 12 weeks before you can fairly judge results. Omega-3 fatty acids incorporate into cell membranes gradually, and coat changes lag behind the underlying biochemistry. Most owners who report improvement notice a softer, glossier coat around week 4 and reduced scratching closer to week 8.

If there's zero change by the three-month mark at an appropriate dose, the itch likely isn't primarily inflammatory-diet-responsive. The ASPCA and most veterinary dermatologists would point you toward a proper allergy workup at that stage. Our dog blog covers how to separate environmental triggers from food triggers before you start swapping bags.

What are the side effects of too much fish oil in dogs?

Overdosing typically shows up as loose stool, fishy breath, and greasy coat, with more serious concerns at sustained high doses: prolonged bleeding time from reduced platelet aggregation, delayed wound healing, and vitamin E depletion. Very high fat intake can also trigger GI upset in dogs prone to pancreatitis.

Introduce fish oil at roughly one-quarter of the target dose for the first week and build up. Dogs with a pancreatitis history need veterinary sign-off before any added fat — the fat content of a full dose can be significant for a small dog on a restricted diet.

Is salmon oil the same as fish oil for dogs?

Salmon oil is a type of fish oil, but its EPA and DHA concentration is usually lower than anchovy or sardine-based oils. Many salmon oils supply 80–150 mg of combined EPA+DHA per 5 ml teaspoon, while concentrated marine oils can deliver 400 mg or more per equivalent serving. Always compare the milligram figure, not the fish species.

Sustainability matters too. Small forage fish like anchovy and sardine sit lower on the food chain, which generally means lower heavy-metal accumulation. The FDA Center for Veterinary Medicine maintains reporting channels for supplement-related adverse events, and reputable manufacturers publish third-party purity testing.

How to choose the right omega-3 supplement for your dog

Pick your format based on your dog's willingness to eat it and your ability to dose accurately. Pump bottles allow fine-tuned dosing for dogs under 10 kg; powders and chews suit dogs who spit out oil; capsules travel well but make partial doses awkward. Whatever you choose, buy a bottle size you'll finish within 60–90 days of opening.

Two supplement lines we're asked about often serve different needs:

Storage is the step most people skip. Fish oil oxidizes on contact with air, light, and heat — an oil that smells sharply rancid has lost potency and may cause GI upset. Keep the bottle in the fridge after opening, and don't leave a pump bottle on a sunny counter through a July heatwave.

If you're feeding a diet that's already fish-forward, factor that in before adding more. Several formulas in our dry dog food range from brands like Acana, Orijen, and Open Farm list whole fish or fish oil high in the ingredient panel, and freeze-dried toppers can contribute as well. For a broader look at what else supports skin, coat, and mobility, browse our guide to dog health supplements or the wider dog wellness essentials page.

One last practical point: pair supplementation with the basics. Regular brushing distributes skin oils, and a gentle shampoo from our dog grooming supplies does more for a dry winter coat than doubling a fish oil dose ever will.

Key takeaway: Dose fish oil by combined EPA and DHA content — roughly 50–75 mg per kg of body weight daily — not by capsule count or bottle weight. Stay below the 370 mg per kg metabolic body weight ceiling, allow 6–12 weeks to judge results, and clear the plan with your veterinarian if your dog takes other medications or has a pancreatitis history.