Quick answer: if your dog is itchy with skin allergies and stiff in the joints, omega-3 is the one supplement ingredient with some evidence for both: the best evidence of the joint actives for arthritis pain, and a small benefit for long-term allergic skin disease. The bigger risk is the chew itself, because many joint chews are flavoured with chicken or other common allergens, and any flavoured extra can spoil a food elimination trial. Agree the plan with your vet first. If your dog's triggers are known and don't include chicken, pork, shellfish or gluten, you could take the label of MedPaw Hip & Joint Chews to your vet and ask whether it suits your dog.
Transparency note: this page is written by MedPaw, which makes a joint supplement. It is general information, not a diagnosis or treatment plan, and it doesn't replace your vet's advice. Sources are linked so you can check them. Checked 9 October 2026.
Get the itch diagnosed first
Itching has many causes: fleas and other parasites, environmental allergies (atopic dermatitis), food allergy, and skin or ear infections that often come with them. Our guide to why a dog is itchy when there are no fleas explains the usual suspects. The type of allergy changes which joint products are sensible:
Allergy type and what it means for a joint supplement
| Situation | What it means for a joint chew | What to ask your vet |
|---|---|---|
| Suspected food allergy, elimination diet in progress | Flavoured chews, treats and supplements can break the trial. Usually best to wait | Can my dog have anything apart from the trial diet? |
| Confirmed food allergy, triggers known | Avoid any product containing those foods, including flavourings | Is every ingredient on this label safe for my dog? |
| Environmental allergy (atopic dermatitis) | Food ingredients matter less, but new products can still upset sensitive dogs | Should we add omega-3 for the skin as well as the joints? |
| On allergy medicines or steroids | Tell your vet about every supplement so they see the whole picture | Does anything need changing or monitoring? |
For guidance only. Your vet diagnoses the cause of itching.
The international treatment guidelines for canine atopic dermatitis say an 8-week elimination diet trial "should permit the diagnosis of food allergy in most dogs", and that the first step in managing allergic dogs is to identify and avoid what sets them off. In a 2016 review of food allergy studies, the foods most often behind dogs' food allergies were beef, dairy, chicken and wheat, followed by soy and lamb.
Omega-3: what it can and can't do
Omega-3 is worth a conversation with your vet because it works on both problems, though modestly:
- Joints: a 2022 review of 72 trials found omega-3 had the strongest evidence for arthritis pain in dogs of the supplements studied, and AAHA's senior care guidelines note its anti-inflammatory effect in joints.
- Skin: the allergy guidelines say oral essential fatty acids "might also provide some small benefit" in long-term atopic dermatitis and can improve coat gloss, but they are "not useful to treat acute flares", and any benefit "might not be seen before two months".
- Not a replacement for allergy treatment. The guidelines say fatty acids are unlikely to work on their own, though they may help some dogs need lower doses of steroids. That decision is your vet's.
Fish oil is the most concentrated source of the omega-3s used in that research. Our guide to omega-3 fish oil for dogs' joints compares options, and if your dog is allergic to fish, see fish-free joint supplements.
When to see your vet
- Facial swelling, hives or breathing difficulty after anything new: this is an emergency
- Itching that gets worse after starting a supplement: stop it and call your vet
- Open sores, smelly or greasy skin, hair loss or sore ears, which may be infected
- Constant licking or chewing of paws (see why dogs lick and chew their paws)
- Limping, stiffness or reluctance to walk, which needs its own check
What helps joints in an allergic dog
Many allergic dogs are also on restricted diets, so non-food help matters even more: keep your dog lean, keep walks short and regular (see low-impact exercise for stiff dogs), add non-slip rugs and a car ramp, and ask about hydrotherapy if your vet thinks it suits.
What the evidence says about joint actives
How the main joint supplement ingredients compare on evidence for joint pain in dogs
| Ingredient | What the 2022 review of 72 trials found |
|---|---|
| Omega-3 (fish oil, green-lipped mussel) | The strongest evidence of the supplements reviewed |
| Glucosamine and chondroitin | Did not relieve pain |
| MSM, hyaluronic acid, Boswellia | Too few good trials to judge on their own |
Source: Barbeau-Grégoire et al., International Journal of Molecular Sciences, 2022.
MedPaw and allergies: the honest version
MedPaw is a chicken and bacon flavour soft chew, and it contains mollusc (green-lipped mussel) and gluten (brewer's yeast). That means it isn't suitable during an elimination diet trial or for dogs allergic to shellfish or gluten, and if your dog reacts to chicken or pork, check the full composition on the tub with your vet first. It doesn't treat allergies, itching or arthritis. For a dog with environmental allergies whose food triggers are known and don't include those ingredients, it may be something to discuss with your vet. Here is the full published list:
MedPaw Hip & Joint Chews: the main amounts per chew on the label, to show your vet
| Ingredient or fact | Per chew, as published |
|---|---|
| MSM | 185mg |
| Glucosamine | 170mg |
| Chondroitin | 70mg |
| Green-lipped mussel | 70mg |
| Boswellia serrata | 30mg |
| Hyaluronic acid | Included (amount not published) |
| Vitamin C | 33mg |
| Vitamin E | 24 IU |
| Zinc | 3mg |
| Format | Soft chicken and bacon flavour chew, 60 per tub |
| Allergens | Mollusc (green-lipped mussel) and gluten (brewer's yeast) |
| What it is | A complementary feed, not a medicine or painkiller |
The full composition and analytical constituents are printed on the tub.
Our recommendation: sort out the itch with your vet first, and only add one new thing at a time so you can tell what helped or hurt. If your vet is happy for your dog to have MedPaw, it combines green-lipped mussel (a source of omega-3) with glucosamine, chondroitin, MSM, hyaluronic acid and Boswellia in one soft chew, with a 60-day money-back guarantee. It isn't a substitute for a fish oil your vet recommends for the skin. Take the label to your vet and ask whether MedPaw Hip & Joint Chews suits your dog. Feeding amounts by weight are on the product page.
For other allergies, see joint supplements for dogs with a chicken allergy and shellfish-free joint supplements.
Joint supplements for itchy dogs: common questions
Can a joint supplement make my dog itchy?
Yes, any new supplement can cause a reaction in some dogs, including itching, red skin or an upset stomach. Flavourings such as chicken can be a trigger for dogs with a chicken allergy. Stop it and speak to your vet if your dog gets itchier after starting.
Does omega-3 help itchy skin in dogs?
A little, in some dogs. International allergy guidelines say oral fatty acids might give a small benefit in long-term atopic dermatitis and improve coat quality, but they don't help acute flares and can take two months to show any effect.
Can my dog have a joint chew during an elimination diet?
Usually not. Flavoured chews, treats and supplements can contain the very proteins the trial is excluding. Ask your vet before giving anything except the trial diet.
Does MedPaw contain chicken?
MedPaw is a chicken and bacon flavour chew, and it contains mollusc (green-lipped mussel) and gluten (brewer's yeast). It isn't suitable for dogs allergic to shellfish or gluten, or during an elimination trial. If your dog reacts to chicken or pork, check the full composition on the tub with your vet before giving it.
Can I give a joint supplement with Apoquel or Cytopoint?
Many dogs take both, but tell your vet about every supplement so they can check it fits your dog's treatment. Don't change allergy medicine doses yourself.
What are the most common food allergies in dogs?
In a 2016 review of published studies, beef, dairy, chicken and wheat were the most common triggers in dogs, followed by soy and lamb.
