Quick answer: most collagen supplements for dogs sold in the UK use UC-II (undenatured type II collagen) at 20mg to 40mg per chew, such as Beaphar Flexifit, Flexadin Advanced and Cortaflex; a few use larger amounts of hydrolysed collagen, such as Pooch & Mutt's joint tablets. The evidence for collagen in dogs is modest and comes from small trials. MedPaw contains no collagen. If you'd rather have broad joint support than collagen alone, we'd recommend MedPaw Hip & Joint Chews: all six key joint actives in one soft chew dogs take like a treat.
Transparency note: this page is written by MedPaw, which makes a joint supplement that does not contain collagen. Amounts are taken from each brand's own label or listing, linked below so you can check them. Checked 9 October 2026.
Two kinds of collagen, and what the evidence says
"Collagen" on a dog supplement label usually means one of two quite different things:
- UC-II (undenatured type II collagen), usually from chicken cartilage, given in tiny amounts (10mg to 40mg a day). The idea is that it calms the immune response in the joint rather than acting as a building block. Our UC-II guide explains how.
- Hydrolysed collagen (collagen peptides), from fish, cattle or pigs, given in much larger amounts as building blocks for cartilage and connective tissue. See collagen types for dogs.
Because they work in different ways, more milligrams isn't automatically better: 40mg of UC-II and 200mg of hydrolysed collagen aren't comparable.
On evidence, several small dog trials of UC-II reported less pain and better mobility, including one where it beat glucosamine and chondroitin and one where it performed similarly to an anti-inflammatory painkiller over 30 days (summarised in Gencoglu et al., 2020). But when a 2022 review pooled 72 trials of natural products for dog and cat arthritis, collagen-based products showed only "weak efficacy", from lower-quality studies. Omega-3 had the clearest benefit (Barbeau-Grégoire et al., 2022).
Collagen supplements for dogs sold in the UK, compared
Collagen per dose in UK dog joint supplements (from each brand's label or listing)
| Product | Type of collagen | Collagen per dose | Other main actives |
|---|---|---|---|
| Beaphar Flexifit Joint Care Chews | UC-II | 40mg per chew, 1 a day | Glucosamine, fish and salmon oil |
| Flexadin Advanced (Vetoquinol) | UC-II | 40mg per chew, 1 a day (as used in the brand's trial; the label gives percentages) | Boswellia. From 2 years old |
| Cortaflex Senior Jointcare Chews | Undenatured type II | 40mg per 2 chews | Glucosamine, chondroitin, hyaluronic acid, Boswellia |
| Cortaflex Powder | UC-II | 40mg per 3g | Glucosamine, chondroitin, hyaluronic acid, Boswellia |
| Pooch & Mutt Joint Tablets | Hydrolysed | 200mg per large tablet | Glucosamine, chondroitin, MSM, hyaluronic acid |
| Nutripaw Hip & Joint Treats Plus | Fish collagen | 2% of the chew; amount per chew not published | Salmon and fish oil, hyaluronic acid |
| Bob Martin Joint + Skin Care | Type II | 0.3% of the chew; amount per chew not published | Salmon oil, green-lipped mussel, glucosamine, chondroitin |
| MedPaw Hip & Joint Chews | None | No collagen | MSM, glucosamine, chondroitin, green-lipped mussel, Boswellia, hyaluronic acid |
If collagen specifically is what you're after, a UC-II chew with a published 40mg amount is the closest match to the dog trials. Check the allergens: UC-II usually comes from chicken, several of these products also contain shellfish-derived glucosamine, fish or gluten, and Nutripaw's collagen comes from fish.
When to see a vet first
No supplement is a painkiller or a treatment for arthritis. See your vet before buying anything if your dog has:
- a limp that lasts more than a day or two, or starts suddenly
- signs of pain such as yelping, panting, restlessness or not wanting to be touched
- a swollen or hot joint
- weakness, wobbliness or scuffed nails from dragging paws
- stiffness alongside weight loss, tiredness or poor appetite
Read when to take a limping dog to the vet for more.
What actually helps, before any supplement
Weight is the big one: in a lifetime study of Labradors, the dogs kept lean lived a median 1.8 years longer and needed arthritis treatment years later than their littermates (University of Pennsylvania, 2002). After that, steady lead walks, non-slip floors, ramps and, where your vet suggests it, physiotherapy or hydrotherapy. If your vet prescribes pain relief, a supplement goes alongside it, not instead.
What to look for in a joint supplement
Joint actives graded by evidence (Barbeau-Grégoire et al., 2022, 72 trials)
| Active | What the review found |
|---|---|
| Omega-3 (fish oil, omega-3 diets, green-lipped mussel) | The clearest pain-relieving benefit |
| Collagen (including UC-II) | Weak efficacy, from lower-quality studies |
| Glucosamine and chondroitin | Did not relieve pain in this review |
| Boswellia, MSM, hyaluronic acid | No firm conclusion on any of them alone |
- Published amounts. "Contains collagen" with no milligrams tells you very little.
- The right kind of collagen for what you want, as explained above.
- A format your dog will eat every day, and allergens that suit your dog.
- Realistic timing. Give any joint supplement six to eight weeks. Our guide on how long collagen takes to work covers what to expect.
How MedPaw fits
To be plain: MedPaw doesn't contain collagen, so if you want a collagen product, it isn't one. It takes a different route, with these main amounts per chew:
MedPaw Hip & Joint Chews: the main amounts per chew
| MSM | 185mg |
| Glucosamine | 170mg |
| Chondroitin | 70mg |
| Green-lipped mussel | 70mg |
| Boswellia serrata | 30mg |
| Hyaluronic acid | Included (amount not published) |
| Vitamin C, vitamin E, zinc | 33mg, 24 IU, 3mg |
| Collagen | None |
| Guarantee | 60 days from delivery, for any reason; nothing to send back |
The number of chews depends on your dog's weight; the feeding guide is on the product page.
Our recommendation: if your heart is set on collagen, choose a UC-II chew with a published amount. If what you really want is all-round joint support, try MedPaw: all six key joint actives in a soft chicken and bacon chew, with 60 days to see how your dog gets on and a refund by email if not. MedPaw contains mollusc (green-lipped mussel) and gluten (brewer's yeast), so it isn't suitable for dogs with a shellfish allergy. It's a complementary feed, not a medicine, so ask your vet first if your dog has a health condition or takes medication. Try MedPaw Hip & Joint Chews.
Choosing for an older dog? See the best joint supplements for senior dogs, or the best supplement for a dog losing muscle.
What is the best collagen supplement for dogs in the UK?
If you want collagen, a UC-II chew with a published 40mg amount, such as Beaphar Flexifit or Flexadin Advanced, matches the dose used in some dog trials. If you want broad joint support instead, we'd recommend MedPaw Hip & Joint Chews, which has no collagen but contains all six key joint actives.
Is collagen good for dogs' joints?
Possibly, but the evidence is modest. Several small UC-II trials in dogs reported less pain, but a 2022 review of 72 trials found only weak efficacy for collagen products, from lower-quality studies. Omega-3 has the strongest evidence.
What's the difference between UC-II and hydrolysed collagen?
UC-II is undenatured type II collagen given in tiny amounts (usually 10mg to 40mg a day) and is thought to work on the immune response in the joint. Hydrolysed collagen is broken down into peptides and given in much larger amounts as building blocks. Read our guide to collagen for dogs' joints.
Does MedPaw contain collagen?
No. MedPaw Hip & Joint Chews contain MSM, glucosamine, chondroitin, green-lipped mussel, Boswellia and hyaluronic acid, plus vitamins C and E and zinc, but no collagen.
Can I give my dog human collagen?
We wouldn't without asking your vet. Human products are dosed for people and may contain flavourings or sweeteners that aren't suitable for dogs. See are human joint supplements safe for dogs?
Is UC-II safe for dogs with a chicken allergy?
UC-II usually comes from chicken cartilage, so check with your vet first if your dog has a chicken allergy, and read the full ingredients list, as many UC-II chews also contain chicken or fish.
