Why Your Dog's Itch Keeps Coming Back: New Research
Skin Allergies Are the #1 Reason Dogs See the Vet. New Research Points to Why the Itch Keeps Coming Back (and Why It Was Never Your Fault)
If you've tried the pills, the shots, the shampoos and the $100 bags of food, and the scratching always returns, researchers studying atopic dog skin may finally have found the missing piece.
It's 2 AM. You're awake again, listening to the jingle of a collar, the thump of a back leg against the mattress, the wet sound of a paw being licked for the hundredth time tonight.
You've done everything right. You went to the vet. You filled the prescriptions. You switched to the expensive food, then the even more expensive food. You bought the oatmeal shampoo, the sprays, the cone.
And it worked. For a while.
Then, a few weeks later, the scratching came back. The paw licking came back. The red patch on the belly came back. And at some point someone, maybe a friend, maybe a forum, maybe even a vet, told you some version of the same thing:
"Some dogs are just itchy. You'll have to manage it."
If that's where you are right now, we want you to know two things.
First, you are not overreacting, and you are not alone.
Skin allergies have been the single most common reason dogs end up at the vet, year after year, in Nationwide's pet insurance claims data. In 2023 they made up about 1 in 5 of all dog claims.Source: Nationwide pet insurance claims analysis [1]
Second, a growing body of veterinary research suggests there's a reason the itch keeps coming back. It's not because you did something wrong. It's because most of what we try is aimed at the wrong layer.
"It worked… until it didn't."
Spend an evening reading dog-owner forums and you'll see the same story told a thousand different ways. Different dogs, different breeds, different countries. The same loop.
Paraphrased from public owner discussions. Names and identifying details removed.
Look at what's usually on the shelf:
- Allergy tabletsRelief → returns
- Anti-itch injectionsGaps get shorter
- SteroidsShort-term only
- Food switch after food switch2 good weeks
- Medicated shampoos & spraysHours, not weeks
To be clear: these are real tools, and many of them are exactly what an itchy dog needs in the moment. Your vet's plan matters.
But notice what they have in common. They all work on the reaction: the itch signal, the inflammation, the trigger. Almost none of them do anything to the skin that the reaction is happening in.
Over the last decade, veterinary dermatologists have been asking a different question: what if the skin itself is part of the problem?
Atopic dog skin is built differently
Your dog's skin isn't just a covering. Its outer layer works like a brick wall: skin cells are the bricks, and a mortar of fats called ceramides seals the gaps. A healthy wall keeps moisture in and pollen, dust mites and other irritants out.
When researchers looked closely at the skin of dogs with atopic dermatitis (the medical name for chronic environmental skin allergies), they found that wall wasn't sealing properly.
The skin barrier research
Studies comparing atopic and healthy dogs have found lower levels of key ceramides in the outer skin layer of atopic dogs, along with a disrupted lipid structure. In 2024, the International Committee on Allergic Diseases of Animals (ICADA) described canine atopic dermatitis as an interplay between skin barrier abnormalities, allergen sensitisation and changes in the skin's microbiome.
Santoro et al. (ICADA), Veterinary Dermatology, 2024 · Yoon et al., Experimental Dermatology, 2011 · Popa et al., Clinical & Experimental Dermatology, 2012
A leaky wall has two consequences. Moisture escapes, so the skin dries out. And irritants get in more easily, so the immune system keeps getting triggered.
That's the part most owners are never told. But there's a second, deeper layer to this story.
What's holding the wall up?
Below that outer wall sits the dermis, the thick, living layer of skin that gives it strength, structure and bounce. It's what the wall is built on.
And the dermis is made mostly of one protein.
Collagen.
In healthy skin, collagen fibres are dense, mature and neatly organised, like a tightly woven mattress the rest of the skin rests on. In 2025, researchers at the Federal University of Ceará in Brazil examined skin samples from atopic dogs under the microscope, next to healthy dogs.
The collagen findings
In the atopic dogs, dermal collagen fibres were reduced in density and disorganised, with a predominance of immature collagen. In healthy control dogs, the fibres were preserved and balanced. A systematic review in the same work, covering 14 studies, pointed to the same pattern: disorganised fibres and impaired maturation of collagen in atopic skin.
Soares, L.G., Morphological and clinical aspects of the skin of dogs with atopic dermatitis, Federal University of Ceará, 2025. Early, small-sample research; more work is needed.
In other words: in atopic dogs, it's not only the outer wall that's weak. The foundation underneath it looks thinner and less organised too.
One problem, showing up in four places
Once you see the skin as a barrier and a foundation, the symptoms that seemed random start to look connected.
The 2 AM scratching
The symptom. Quiet all day, then the scratching starts the moment the house goes still. The collar jingle that wakes you up three times a night.
Why it happens. A leaky barrier lets irritants in around the clock, from bedding dust mites to pollen carried in on the coat. At night there's nothing to distract your dog from the itch, so it takes over.
The paw licking that never stops
The symptom. Rust-coloured fur between the toes. Licking that starts the second you sit down. Paws that smell like corn chips.
Why it happens. Paws touch everything: grass, floors, pavement. Where the barrier is weakest, irritants get the easiest way in. And the licking itself softens the skin, so the barrier gets weaker still.
Hot spots that heal and come back
The symptom. A red, raw patch that finally closes up, then reappears in the same spot, or a new one, a few weeks later.
Why it happens. Treatment calms the flare, but the skin underneath is still fragile. The next scratch breaks it open again. Without a stronger foundation, the same weak spots keep failing.
The dull, flaky coat
The symptom. Dandruff on the couch. A coat that feels dry and brittle instead of soft. A dog that used to shine and doesn't any more.
Why it happens. When moisture escapes through a leaky barrier, the skin dries out. Dry skin flakes, and the coat that grows from it loses its softness and shine.
Different symptoms. Same skin.
Which leads to the question owners always ask next: how does it get this bad?
The loop that feeds itself
Here's the cruel part. Once the barrier is weak, the itch itself makes it weaker.
Every scratch and every lick damages the skin a little more. Damaged skin lets more irritants in. More irritants mean more itch. Round and round.
Add in the things that quietly drain the skin's foundation over time, such as age (collagen production slows as dogs get older) and diets built mostly on muscle meat (collagen lives in skin, cartilage and connective tissue, not in lean meat), and you get a loop that can run for years.
That's also why many owners notice it getting worse each season instead of better.
If you have one of these breeds, you've probably lived this
ICADA describes canine atopic dermatitis as hereditary: some dogs are simply born with skin that's more prone to this pattern. It isn't something you caused, and it isn't something a better owner would have prevented.
But it does mean that for these dogs, the skin needs more support, not less, and for life, not just for one flare.
Two different jobs, and most dogs only get help with one
Modern itch medications are genuinely good at what they do. Some block the itch signal on its way to the brain. Others neutralise one of the messenger molecules that creates the itch. Steroids shut down inflammation broadly.
What none of them are designed to do is rebuild the barrier or the collagen foundation underneath it.
Job 1 · Silence the alarm
Calm the itch signal and inflammation so your dog gets relief now.
Meds, injections, steroidsJob 2 · Repair the wall
Give the skin the building blocks it needs so the alarm gets triggered less often.
Usually skippedTurn off the alarm without repairing the wall, and the alarm keeps going off. That's the "it worked until it didn't" pattern almost every owner describes.
Feeding the foundation, every single day
If the skin's foundation is thin and disorganised, the logical next step is to give the body more of what that foundation is made of, consistently, from the inside.
That idea isn't new in human research. Oral collagen has been studied in dozens of randomised trials.
Oral collagen & skin hydration
A 2023 meta-analysis pooled 26 randomised controlled trials with 1,721 participants and found that hydrolysed collagen supplementation significantly improved skin hydration and elasticity compared with placebo. Duration mattered: results built over weeks of consistent use.
Pu et al., Nutrients, 2023. Note: this research was carried out in people, not dogs.
In dogs, collagen research has so far focused mainly on joints, and the results are encouraging there too:
Collagen peptides in dogs
In a 12-week, double-blind study of dogs with osteoarthritis, the group given bioactive collagen peptides showed improved gait measurements on force-plate testing and better owner-rated quality of life, compared with a group given omega-3 and vitamin E.
Dobenecker et al., PLoS One, 2024 (41 dogs enrolled, 31 completed).
That's exactly the thinking behind the formula we're about to show you.
A liquid collagen built for the skin's foundation (with a bonus for joints)
We created Move & Glow because we were living the same loop as you. We wanted something that did Job 2: something that gives the skin back its building blocks, every day, in a form a dog will actually take.
It's not a drug. It doesn't block anything or numb anything. It's a food supplement designed to support the skin from the inside, so it can work alongside whatever your vet has your dog on.
Collagen Types I & IIIthe foundation
The two collagen types found in skin. Type I is the mature, structural collagen; Type III is the younger form it develops from. Together they support skin structure, elasticity and hydration.
Hyaluronic Acidthe moisture lock
A molecule that holds water in the skin. Supports hydration where a leaky barrier lets moisture escape, and helps with dry, flaky skin.
Collagen Type IIjoint bonus
The collagen type found in joint cartilage. A bonus for active and senior dogs (that's the "Move" in Move & Glow).
Glucosaminejoint bonus
Supports joint flexibility and cartilage, working alongside Type II collagen.
Alcohol-free · No artificial colours · No added sugar.
One dropper on food. That's it.
Once a day, on food or in water. Most dogs love the natural chicken flavour, so there's nothing to hide in cheese and nothing to spit out.
- No pills
- No chews to refuse
- No diet change
- No injections
- No prescription
You don't have to stop anything to start
Because Move & Glow is a food supplement and not a medication, many owners add it alongside their dog's existing itch plan. It's doing a different job.
We always recommend letting your vet know you're adding it, especially if your dog is on medication, pregnant, nursing or has a health condition. Never stop or reduce a prescribed medication without your vet's advice.
Skin rebuilds in cycles, not overnight
A dog's outer skin renews roughly every three weeks [6]. Collagen is a building block, not a fast-acting drug, so the realistic way to judge it is over several of those cycles:
- Weeks 1–3 · First skin cycleBuilding the daily routine. Some owners notice less scratching early; many don't yet, and that's normal.
- Weeks 4–6 · Second cycleThis is when owners most often start to notice calmer nights and less licking.
- Weeks 6–8 · Third cycleCoat feels softer, flakes reduce, skin looks calmer.
- Week 12 · Full courseJudge it here. That's exactly why the guarantee is 90 days.
Every dog is different and results vary.
The loop doesn't pause on its own
Remember the loop: weak skin leads to itch, itch leads to scratching, scratching leads to weaker skin.
Every week it runs, there's more damage to repair. Hot spots that keep reopening. Paws licked raw. Seasons that start earlier and end later.
Which means the skin your dog has today, whether they're one year into this or eight, is the easiest it will ever be to support. Every month that passes is another month of the loop.
Real results from real dog owners.
See why dog parents are making Move & Glow part of their daily routine.
I honestly can't believe the difference! 😭 I tried so many shampoos, creams, and supplements for my Golden Retriever, but nothing seemed to help for long. She was constantly scratching and licking her belly, and it was heartbreaking to watch. Her skin looks so much healthier now, her coat is softer, and she's finally back to her happy, playful self. I just wish I'd found this sooner!
I was so tired of seeing my poor boy constantly licking and chewing his paws. I'd tried changing his food, special shampoos, paw balms... honestly, you name it. Nothing seemed to make a lasting difference. Now his paws look so much better, the reddish stains have faded, and he's not obsessively licking them anymore. Seeing him comfortable and relaxed again means everything to me
My dog had really bad dry, flaky skin for months. Every time I brushed him, there were little white flakes everywhere. I tried different shampoos, changed his food, even bought some expensive oils, but nothing really helped. Since I started adding these drops to his food, I've noticed a big difference. His coat looks healthier, feels much softer, and there's barely any flaking anymore. Honestly wasn't expecting much after trying so many things, but I'm really happy with the results.
guarantee
Give it the full course, on us
Skin takes weeks to rebuild, so we give you 90 days, enough for several full skin cycles. If Move & Glow isn't right for your dog, email us within 90 days and we'll refund you. No hoops.
Start Move & Glow today
90-day money-back guarantee on every option · Secure checkout
Can I use it with Apoquel, Cytopoint or other meds?
Move & Glow is a food supplement, and many owners use it alongside their vet's plan. Please check with your vet first, and never stop or change a medication without their advice.
How long until I see a difference?
Skin renews in roughly three-week cycles, so most owners judge it over 4–8 weeks and the full 12-week course. Results vary from dog to dog.
Will my dog actually take it?
It has a natural chicken flavour most dogs love. Add it to food or drinking water, with no pills to hide.
My dog has a chicken allergy. Is it safe?
Move & Glow uses a natural chicken flavour, not chicken meat. If your dog has a confirmed chicken allergy, check with your vet first.
How long does a bottle last?
One 60 mL bottle lasts about 60 days for dogs under 25 lbs, 30 days for 25–75 lbs, and 20 days for dogs over 75 lbs.
What if it doesn't work for my dog?
Email us within 90 days and we'll refund you. That's the whole process.
- Nationwide. Most common conditions that prompt veterinary visits (2023 claims data). news.nationwide.com
- Santoro D, et al. (ICADA). Update on the skin barrier, cutaneous microbiome and host defence peptides in canine atopic dermatitis. Veterinary Dermatology. 2024;35(1):5-14. doi:10.1111/vde.13215. pubmed.ncbi.nlm.nih.gov
- Yoon JS, et al. Alteration of stratum corneum ceramide profiles in spontaneous canine model of atopic dermatitis. Experimental Dermatology. 2011. pure.jbnu.ac.kr
- Soares LG. Morphological and clinical aspects of the skin of dogs with atopic dermatitis. Federal University of Ceará. 2025. repositorio.ufc.br
- Pu SY, et al. Effects of oral collagen for skin anti-aging: a systematic review and meta-analysis. Nutrients. 2023. pubmed.ncbi.nlm.nih.gov
- Royal Canin Veterinary Focus. The skin barrier in canine atopic dermatitis. 2024. vetfocus.royalcanin.com
- Dobenecker B, et al. The oral intake of specific Bioactive Collagen Peptides (BCP) improves gait and quality of life in canine osteoarthritis patients. PLoS One. 2024. pmc.ncbi.nlm.nih.gov
- Popa I, et al. The lipid alterations in the stratum corneum of dogs with atopic dermatitis are alleviated by topical application of a sphingolipid-containing emulsion. Clinical & Experimental Dermatology. 2012;37:665-671.
This article is published by Tivana, the maker of Move & Glow. It is for general information only and is not veterinary advice.
Move & Glow is a food supplement for dogs and is not intended to diagnose, treat, cure or prevent any disease. The studies cited were not conducted on Move & Glow. Results vary. Always talk to your veterinarian before changing your dog's diet or medication, and see your vet if your dog's skin is broken, infected or getting worse.
Owner comments are paraphrased from public online discussions and are not reviews of Move & Glow.
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