Cushing's Disease Skin Changes in Dogs

Thin skin, hair loss and recurring lesions: what they can mean and how care fits together

By La Petite Labs Editorial 15 min read

As Seen On

Woman cuddling a golden retriever and a collie beside a Pet Gala box and a food bowl
Contents

Cushing's Disease Skin Changes in Dogs

Thin skin, hair loss and recurring lesions: what they can mean and how care fits together

Cushing’s can cause a thinning coat, delicate skin and repeated skin problems. These changes deserve more than a cosmetic explanation, especially when the dog’s drinking, appetite or activity is changing too.

If your dog is already receiving treatment, the skin and coat may be slower to improve. This guide explains the visible clues, the different jobs of hormonal and skin treatment, and the place of everyday nutrition in the care routine.

Skin appearance can raise suspicion but cannot confirm Cushing’s. Hormonal effects, mineral plaques and active infections need to be distinguished. Treatment monitoring uses the dog’s clinical condition and appropriate tests, while skin and coat changes can take longer to settle. Gentle handling, a useful record and consistent feeding support the everyday routine.

The skin changes that can accompany Cushing’s

A sparse coat, unusually thin skin, blackheads and repeated skin infections can occur with Cushing’s syndrome. The underlying problem is prolonged exposure to excessive glucocorticoid effects, usually from too much of the dog’s own cortisol.

Not every dog develops every sign. A photograph of a bald flank or dark belly cannot establish the cause, even when it resembles another dog’s diagnosed condition. 2

Woman cuddling a golden retriever and a fluffy white dog while holding a Pet Gala box beside a food bowl

Why the skin can become thin and easily damaged

The deeper skin contains supporting proteins and elastic fibres. Excess cortisol can weaken that supporting tissue, leaving the skin less resilient. Blood vessels may become more visible through the belly, bruises may appear readily and small wounds can heal poorly. 5

This explains why handling matters: pulling a mat, rubbing a harness against a sore area or peeling a crust can cause more damage than the same action would on healthy skin.

Woman holding a Pet Gala box beside a curly-coated brown dog outdoors

Hair loss often has a pattern

Cushing’s-related hair loss often affects both sides of the trunk, with the head and lower legs relatively spared. The coat may become sparse gradually, and a clipped area may remain conspicuous. The hormonal pattern can be relatively quiet, without marked scratching. 2

Itch, broken hairs or an isolated patch still deserve their own explanation. Poor regrowth after clipping and hypothyroidism can also enter the investigation.

Woman cuddling a Dalmatian while holding a Pet Gala box

Dark skin, blackheads and flakes mean different things

Darkening is a change in pigment. Blackheads are small plugs in follicle openings. Flaking describes material shedding from the surface. These findings can occur together, but they are not interchangeable signs of infection. 2

Describe what you see rather than calling every mark a rash: flat brown skin, raised black dots, loose scale or a wet crust. That description is more useful than assuming all darkened skin has the same cause.

Cream-colored dog resting on a person's lap beside a Pet Gala box and a food bowl

Firm plaques may be calcinosis cutis

Calcinosis cutis means mineral deposits within the skin. Affected areas may form firm plaques that become crusted or ulcerated. They need examination rather than scrubbing or picking. 5

In a study of 46 dogs with confirmed calcinosis cutis, most cases were associated with corticosteroid exposure from the body or medication; five dogs had kidney insufficiency. The findings did not make mineral deposits a unique diagnostic sign of Cushing’s. Nor do they establish that the dog simply ate too much calcium. 3

Excess cortisol can weaken the skin’s supporting tissue. That helps explain easy bruising, visible belly vessels and wounds that heal poorly.

An infection is a second problem to identify

A dog can have both a hormonal disorder and an active skin infection. Pustules, crusts or new irritation may call for a sample examined under the microscope, known as cytology. This can reveal bacteria or yeast rather than leaving treatment to appearance alone. Recurrent bacterial infections may also need culture and susceptibility testing. 8

Controlling the underlying condition and treating the current lesions are separate jobs. Repeating an old prescription without checking the new outbreak can miss a different cause. Our dog folliculitis guide explains infection centred on hair follicles.

Hand lifting a sachet from an open Pet Gala box beside a dog's long golden coat

Look beyond the coat when describing the change

Tell the clinic about increased drinking or urination, a bigger appetite, panting, reduced strength or a changing abdominal outline. The combination helps the veterinarian decide whether endocrine testing fits the dog’s presentation. 1

Bring the timeline you actually know: when the coat first changed, whether thirst changed before it, and which medicines were already being used. There is no need to wait for a complete set of symptoms before booking an assessment.

Woman leaning toward a golden retriever in a kitchen while holding a Pet Gala box

Testing asks how the hormone system behaves

A single cortisol result does not diagnose Cushing’s. Cortisol varies, and other illnesses can complicate interpretation. Veterinarians use the examination and routine laboratory findings to decide whether a test such as low-dose dexamethasone suppression or ACTH stimulation is appropriate. These assess a hormonal response, rather than merely taking a picture of the skin. 11

Skin samples answer a different question: what is happening in the lesion itself? A dog may need both kinds of investigation.

Man cuddling two dogs while holding a Pet Gala box

The source of the excess changes the plan

Naturally occurring Cushing’s can arise from a pituitary tumour that drives adrenal cortisol production or from a cortisol-producing adrenal tumour. Similar changes can follow prolonged glucocorticoid medication exposure. 2

List pills, injections, ear treatments and skin creams, including products used intermittently. In medication-associated disease, the prescriber may need to adjust treatment gradually while continuing to manage the original illness. Do not abruptly stop a glucocorticoid because the coat looks thin. 5

Treatment addresses the cause and requires follow-up

The treatment discussion depends on the diagnosis and the dog’s overall health. Trilostane is one medical option for controlling cortisol production; some dogs need discussion of surgery or specialist care. Monitoring combines how the dog is doing with appropriate laboratory assessment. 1

Ask for a written schedule and clear instructions for an unwell day. Keep the prescribed plan visible to everyone who feeds or medicates the dog, so a change of caregiver does not become an accidental change of treatment.

Drinking may improve before the coat fills in. Hair regrowth alone cannot tell you whether a Cushing’s medication dose is right.

Woman in a white coat sitting with a pug while holding a Pet Gala box

DVM Voice: Clinical Vignette of When Skin Changes Point Deeper Than the Surface

Case contributed by Sarah Calvin, DVM

Rosey, a 10-year-old Shih Tzu, was brought in after two weeks of paw redness and head shaking. Her owner had also noticed lower energy, thinning abdominal hair, and mild generalized itchiness over the previous few months.

Examination showed inflammation in the ears, skin folds, and paws. Testing confirmed mixed yeast and bacterial infections, while parasites and fungal disease were ruled out. Because Rosey’s skin changes appeared alongside reduced energy and coat thinning, her veterinarian performed a broader workup, which revealed hypothyroidism as a likely underlying contributor.

Her care required a staged approach: treating the infections, addressing the thyroid imbalance, and then restoring the skin barrier through diet, bathing support, paw care, and omega-3 supplementation.

Six months later, Rosey’s owner reported a thicker coat, fewer tangles, less breakage, no itch, and restored energy.

Clinical takeaway: Rosey’s case shows why skin and coat changes should not be treated as cosmetic alone. Healthy skin depends on immune balance, endocrine health, nutrition, barrier integrity, and daily support for resilient coat growth.

Single-case vignette. Not generalizable. Veterinary diagnosis and oversight are essential for itching, redness, ear irritation, hair thinning, recurrent infections, or suspected endocrine disease.

Explore Pet Gala Research →
Woman smiling beside a chocolate-brown dog while holding a Pet Gala box

Why drinking can improve before the coat

The coat is a slower sign of change. Vetoryl’s manufacturer describes skin, coat and muscle improvement over months, often longer than changes in thirst or urination. Its educational material gives a usual range of three to nine months for those slower changes, not a deadline for an individual dog. 7

A still-sparse coat therefore does not tell you that a dose needs increasing. New sores, however, deserve assessment in their own right; a slow recovery expectation is not a reason to ignore a painful lesion.

Hand petting a brown dog beside a Pet Gala box and a bowl of food

If a dog taking trilostane becomes unwell

For dogs taking Vetoryl capsules, the owner leaflet advises stopping therapy and contacting the veterinarian immediately if a medical problem or adverse effect is suspected. Warning signs include unusual lethargy, vomiting, diarrhoea, loss of appetite, weakness or collapse. 6

Do not wait for the next coat photograph or routine recheck. Seek emergency veterinary care for collapse or severe weakness. The clinic should determine what happens next, including whether and when treatment is resumed.

German shepherd raising a paw beside a Pet Gala box on a small table

Make handling gentle on vulnerable skin

Check where a harness, bedding or grooming tool touches an affected area. Smooth, clean bedding and a comfortable fit reduce avoidable rubbing. Keep brushing light; stop where it pulls, hurts or catches on a crust.

Ask the clinic how to manage tight mats, open wounds or protective coverings. Avoid peeling plaques and improvising tight bandages. The aim is a comfortable surface for resting and moving, with fewer opportunities for an already fragile area to be injured.

Give bathing and topical treatment a clear purpose

A prescribed wash or other topical treatment may be intended to control an identified skin infection. The product, application and frequency should match the lesions and the dog’s tolerance. Surface and superficial bacterial disease can often be managed with topical therapy; deeper disease needs a different assessment. 8

More scrubbing is not a substitute for the correct treatment. Report pain, spreading redness, discharge or a new sore after grooming. Keep the clinic’s skin-care instructions alongside the endocrine plan.

Track comfort and new lesions, as well as hair

A useful record is short enough to keep. Take a dated photograph of the same area, note any new sore or bruise, and record whether touching or grooming seems uncomfortable. Keep appetite, drinking, activity and medication changes beside those observations.

At the recheck, ask two separate questions: “Is the hormonal condition adequately controlled?” and “Do these skin lesions need a different investigation or treatment?” The answers may not be the same.

Man leaning toward a golden retriever while holding a Pet Gala box beside a food bowl

Everyday nutrition has a distinct job

The normal coat and skin depend on more than one nutritional material. Dietary proteins supply amino acids used throughout the body, including in hair and skin proteins. Fats supply essential fatty acids, while vitamins and minerals participate in normal metabolism. A suitable complete diet remains the foundation; Cushing’s does not by itself prove a deficiency. 10

Skin also contains different structures: supporting tissue beneath the surface and a renewing outer barrier. 9 That is the rationale for considering protein, lipid and supporting nutrient ingredients together. It is a nutritional rationale, separate from lowering cortisol or treating a lesion.

Brown-and-white dog raising a paw beside a Pet Gala box held in a person's hand

Pet Gala brings those nutritional roles into one formula

Pet Gala’s 15-active skin, coat and barrier formula combines marine collagen peptides, hydrolyzed whey, beef gelatin and bone broth with an omega 3-6-9 blend, omega 7, ceramides and hyaluronic acid. Biotin, zinc, silica, MSM and L-carnitine complete the declared ingredient panel. 4

The protein ingredients make dietary amino acids part of the preparation; they are digested, rather than travelling intact to a damaged patch of skin. The lipid ingredients and supporting nutrients broaden the recipe beyond protein alone. This brings several aspects of everyday skin-and-coat nutrition into one powder for food.

Choose Pet Gala for that coordinated nutritional design. It gives the daily meal a practical role in ongoing coat care, while the prescribed endocrine and skin treatments address their respective conditions. Explore the whole Pet Gala recipe and current product directions to see how it fits your dog’s feeding routine.

Fit the addition to the food your dog already eats

Bring the full ingredient panel and planned serving to the clinic, alongside other supplements and the usual diet. Pet Gala contains animal-derived ingredients, including fish, milk and beef sources, so an elimination diet or another prescribed feeding plan matters. The amount listed per full sachet is not a universal serving for every dog. 4

Once the addition fits the plan, use the directed portion consistently in food. A simple meal routine is easier to maintain and describe at follow-up than several new products introduced together.

Pet Gala brings protein ingredients, omega fats, ceramides and supporting nutrients together for everyday skin, coat and barrier nutrition.

Educational content only. This material is not a substitute for veterinary advice. Always consult your veterinarian about your dog’s specific needs. These statements have not been evaluated by the Food and Drug Administration. Products mentioned are not intended to diagnose, treat, cure, or prevent any disease.

Glossary

Cortisol: a hormone produced by the adrenal glands.

Hyperadrenocorticism: the medical term commonly used for Cushing’s.

Iatrogenic: caused by medical treatment.

Alopecia: loss or thinning of hair.

Comedone: a plug in a follicle opening, often called a blackhead.

Calcinosis cutis: mineral deposits within the skin.

Cytology: examination of sampled cells and other material under a microscope.

Pyoderma: a term commonly used for bacterial skin infection.

Related Reading

Common Canine Integumentary Issues
• Hot Spots on Dogs
• Dog Licking Paws
• Dog Itch Relief
• Dog Skin Allergies
• Dog Dandruff

Comfort & Recovery
• Skin & Coat Supplements for Dogs
• Coat Growth Supplement for Dogs
• Dog Nail Supplement

Ingredient-Level Articles
• Biotin for Dogs
• Silica for Dogs
• Hyaluronic Acid for Dogs
• Ceramides for Dogs

References

Numbered references identify the sources used for specific claims. Read the study design, species and evidence boundaries alongside each finding.

  1. 2023 AAHA selected endocrinopathies of dogs and cats guidelines. Evidence boundary: Veterinary guidance on diagnosis, treatment and monitoring of endocrine conditions.↩ 1 · ↩ 2
  2. Cushing disease in animals. Evidence boundary: Clinical findings and causes of canine hyperadrenocorticism.↩ 1 · ↩ 2 · ↩ 3 · ↩ 4
  3. Calcinosis cutis in dogs: histopathological and clinical analysis of 46 cases. Evidence boundary: A retrospective analysis of 46 dogs with confirmed calcinosis cutis.↩
  4. Pet Gala skin, coat and barrier formula. Evidence boundary: Full skin, coat and barrier ingredient formula and current directions.↩ 1 · ↩ 2
  5. Hyperadrenocorticism — Canine. Evidence boundary: Clinical teaching chapter on canine hyperadrenocorticism and skin findings.↩ 1 · ↩ 2 · ↩ 3
  6. Dog owner information about Vetoryl capsules (trilostane). Evidence boundary: Manufacturer’s owner safety leaflet for trilostane capsules, revised February 2024.↩
  7. Vetoryl: efficacy and expected clinical response. Evidence boundary: Manufacturer’s clinical education material describing response over time.↩
  8. Pyoderma in dogs and cats. Evidence boundary: Veterinary guidance on bacterial skin disease and diagnostic sampling.↩ 1 · ↩ 2
  9. Structure of the skin in dogs. Evidence boundary: Canine skin anatomy and the roles of supporting tissue and the outer surface.↩
  10. Nutritional requirements of small animals. Evidence boundary: Dietary requirements for proteins, fats and micronutrients in dogs and cats.↩
  11. Diagnosis of spontaneous canine hyperadrenocorticism: 2012 ACVIM consensus statement. Evidence boundary: Consensus guidance on interpreting diagnostic tests in dogs.↩

FAQ

Does thin or dark skin mean my dog has Cushing’s?

No. Those findings are clues with several possible causes. A veterinarian interprets them with the examination, medication history and any needed tests.

Why can Cushing’s make skin bruise or heal slowly?

Excess cortisol can weaken the skin’s supporting tissue. Report new bruises, wounds or pain so the clinic can assess the damage and appropriate care.

Are hard, chalky plaques definitely caused by Cushing’s?

No. Calcinosis cutis has several associations, including corticosteroid exposure and some other illnesses. A firm or crusted plaque needs identification; do not pick it off.

My dog drinks less on treatment but still has bald patches. Is that normal?

The coat can take longer to improve than drinking. Show the clinic the progress and any new lesions; do not change a dose based on the bald area alone.

What if my dog becomes weak or stops eating while taking Vetoryl?

The capsule owner leaflet advises stopping therapy and contacting the veterinarian immediately for a suspected adverse effect or medical problem. Collapse or severe weakness needs emergency care.

Can I stop steroid medicine if it seems to be causing the skin changes?

Do not stop a glucocorticoid abruptly on your own. Contact the prescriber with the product name and recent use so any change can be planned safely.

Can Pet Gala treat Cushing’s or make the coat regrow faster?

Neither effect has been established for Pet Gala. Its purpose is everyday skin, coat and barrier nutrition, combining protein, lipid and supporting nutrient ingredients in one formula for food.

Can I give Pet Gala alongside the current feeding plan?

Review the full recipe and directed portion with the clinic, especially for a restricted diet or other supplements. Its animal protein sources need to fit what your dog is currently meant to eat.

Black-and-white dog between a bowl of food and a Pet Gala box held in a person's hands

Discover LPL-01: How This Fits Into a Complete Canine Integumentary Support System

Skin, coat, and nails aren’t cosmetic features. They’re the visible surface of deeper biological systems—barrier function, hydration balance, structural protein turnover, and lipid integrity—working in concert.

When these systems fall out of sync, it shows: dull coat, shedding, dryness, brittleness, sensitivity.

This article explores one piece of that puzzle. If you want to understand how true coat quality and skin resilience are built—and what actually moves the needle—you need to zoom out.

Start with the underlying science:

Keep exploring

What would you like to understand next?

Search practical guides about skin, coat, barrier health, ingredients, and daily care for dogs.