Hair loss in dogs — when is it normal and when is it a disease?

Is hair loss in dogs normal?

Yes, in certain quantities and at specific times of the year, hair loss in dogs is completely natural. Dogs shed throughout the year, and twice a year in spring and autumn the intensity of this process increases significantly. This is so-called seasonal shedding, during which a dog gets rid of old undercoat and exchanges its coat for a new one, adapted to the upcoming season. Concern should arise when hair falls out unevenly, when bald patches appear, when shedding is accompanied by itching, skin redness or changes in the dog's behaviour.

Hair loss in dogs — normal or disease? How to distinguish

It is most likely normal when:

• shedding intensifies in spring and autumn
• hair falls out evenly across the entire body
• the dog's skin looks healthy — without redness, flaking and changes
• the dog is active, eats normally and does not scratch excessively
• new hair regrows regularly

It is a signal to visit a veterinary surgeon when:

• bald patches or thinning appear in specific areas
• the dog scratches, licks or bites its skin intensively
• the skin is red, flaking or ulcerated
• hair loss is sudden and intense with no connection to the season
• the dog's hair falls out in clumps
• shedding is accompanied by changes in appetite, lethargy or excessive thirst

Hair loss in dogs — 8 most common causes

1. Seasonal shedding — natural coat exchange

Twice a year in spring and autumn hair loss in dogs increases dramatically. This is a physiological process of adapting the coat to changing environmental temperature. In spring, a dog gets rid of thick winter undercoat, in autumn light summer coat. Seasonal shedding usually lasts 2–6 weeks and is more intense in breeds with undercoat German Shepherds, Labrador Retrievers, Golden Retrievers, Huskies and Samoyeds.
What helps: regular brushing at least 3–4 times a week during shedding significantly speeds up coat exchange and reduces the amount of hair in the home.

2. Nutritional deficiencies — poor diet weakens coat

Hair loss in dogs often results directly from deficiencies in the diet. The coat is one of the last organs to receive nutrients — when food is poor, a dog's body prioritises more important functions, and the coat suffers first.
Key ingredients for a dog's healthy coat:

• Omega-3 and omega-6 fatty acids — responsible for skin hydration and coat shine. Their deficiency manifests itself as dull, brittle hair and flaking skin.
• High-quality protein — coat is built in over 90% from protein (keratin). Food with low meat content or based on plant protein does not provide amino acids essential for building a healthy coat.
• Zinc — zinc deficiency in dogs causes hair loss, skin flaking and skin changes. Huskies and Malamutes are particularly at risk.
• Biotin and B-group vitamins — support hair follicle regeneration.

If your dog is losing excessive hair, the first step should be to check the composition of their food particularly the content of animal protein and fatty acids. Food with a high meat content, flaxseed and natural oils significantly improves the condition of the coat within 4–8 weeks of changing diet.

3. Allergies — skin and food

Allergies are one of the most common causes of excessive hair loss in dogs outside the shedding season. They can have two sources:

• Food allergy — a reaction to a food ingredient, most commonly protein (chicken, beef, wheat). Symptoms include hair loss, intense scratching, skin redness, recurrent ear infections and digestive problems.
• Environmental allergy (atopy) — a reaction to pollen, dust mites, mould or grass. Symptoms worsen seasonally or after contact with a specific allergen.

How to recognise a food allergy: symptoms appear throughout the year, not just seasonally. The dog scratches mainly around the paws, belly, armpits and ears.
The solution when suspecting a food allergy is an elimination diet for a minimum of 8–12 weeks the dog eats only food with a single source of protein that they have not eaten before. Food with lamb as the only animal protein is often the first choice for elimination diets lamb is rarely an allergen in dogs that previously ate mainly chicken or beef.

4. Parasites — fleas, ticks and mange

External parasites are a common and easy-to-overlook cause of hair loss in dogs. Fleas cause intense scratching and hair chewing — particularly around the tail and rear end. Mange (sarcoptic mange) causes severe itching, skin redness and hair loss in characteristic places — on the ears, elbows, belly.
How to recognise it: the dog scratches intensely, hair falls out in specific areas, and redness or scabs are visible on the skin.
Regular antiparasitic prophylaxis both external and internal is the foundation for preventing these problems.

5. Hormonal diseases

Hormonal imbalances are one of the more serious causes of hair loss in dogs and require veterinary diagnosis.

• Hypothyroidism — insufficient production of thyroid hormones. Symptoms: symmetrical hair loss on the sides of the body, weight gain without diet change, lethargy, exercise intolerance.
• Hyperadrenocorticism (Cushing's disease) — excessive cortisol production. Symptoms: hair loss, enlarged belly, excessive thirst and urination, muscle weakness.
• Sex hormone disorders — especially in unspayed females and unneutered males. Uneven hair loss around the belly and hind legs.

If hormonal disease is suspected, blood tests are necessary full blood count and hormone panel.

6. Stress and separation anxiety

Hair loss in dogs can be a direct effect of chronic stress. House moves, change of owner, a new animal in the home, separation anxiety all of this can cause excessive shedding. The mechanism is similar to that in humans stress disrupts hormonal balance, which directly affects the hair growth cycle.
How to recognise it: hair loss appeared or worsened after a specific stressful event. The dog simultaneously shows other signs of stress excessive paw licking, restlessness, destructive behaviour.

7. Skin Diseases and Ringworm

Skin ringworm (dermatophytosis) causes characteristic circular bald patches — most often on the head, ears and paws. The lesions are clearly defined and may have flaking skin in the centre.
Bacterial skin infection (pyoderma) manifests itself with pustules, scabs and hair loss in affected areas. It requires treatment with an antibiotic prescribed by your vet.

8. Grooming Mistakes

Brushing too infrequently especially in long-haired breeds leads to matting which mechanically pulls out the coat. Bathing too frequently or using unsuitable shampoos destroys the skin's natural lipid barrier and weakens hair follicles.
The rule is simple: bathe your dog no more than every 4–6 weeks using a shampoo designed for dogs never for humans.

How to Reduce Hair Loss in Dogs — Practical Methods

• Regular brushing is essential — it removes dead undercoat before it ends up on furniture and clothes, stimulates the skin and improves circulation to hair follicles. During seasonal shedding, brush your dog daily.
• A diet rich in fatty acids directly translates to coat condition. Food with high meat content, linseed and salmon oil reduces excessive hair loss within several weeks.
• Omega-3 supplementation — salmon or sardine oil added to food is one of the most effective and natural ways to improve coat condition.
• Regular parasite prevention eliminates one of the more common causes of skin problems.
• Avoid stress — routine, calm and a predictable environment directly affect coat condition.

Hair Loss and Diet — What to Feed for a Healthy Coat?

A dog's coat condition is a mirror reflection of its diet. Food low in animal protein, fatty acids and micronutrients will always result in poor coat quality regardless of how many supplements you add. Look for food that contains: over 50% animal protein, linseed or salmon oil as a source of omega-3, zinc and biotin in the mineral composition and no unnecessary grain fillers as main ingredients.
Look4dog CARE Food contains linseed, natural vegetables and over 50% animal protein ingredients that genuinely support skin and coat condition. Available in beef and lamb versions — flavour rotation additionally reduces the risk of food allergies. For dogs with sensitive skin and dermatological issues, a good choice is KEBZOO Wet Food with Lamb — simple formula with a single protein source, ideal for elimination diets or dogs with confirmed food allergies.

When to Visit the Vet About Hair Loss?

Don't wait when:

• bald patches or noticeable thinning appear
• your dog scratches until bleeding or has visible skin lesions
• hair loss is sudden and very intense
• it is accompanied by other symptoms — weight change, excessive thirst, lethargy
• the problem persists for over 4–6 weeks without improvement despite diet and grooming changes

Your vet may order blood tests, skin swabs, allergy tests or skin biopsy depending on the clinical picture.

FAQ — Hair Loss in Dogs

Is hair loss in dogs normal?
Yes — seasonal shedding in spring and autumn is a natural process. Uneven hair loss, with bald patches or accompanying skin symptoms, is concerning.
How long does shedding last in dogs?
Seasonal shedding typically lasts 2–6 weeks. The intensity depends on the breed — dogs with undercoats shed more intensely and for longer.
Which dog breeds shed the most?
Breeds with dense undercoats shed the most: German Shepherd, Labrador Retriever, Golden Retriever, Siberian Husky, Samoyed, Border Collie and Bernese Mountain Dog.
What should you give your dog for hair loss?
Omega-3 fatty acids are most effective — salmon oil added to food. Before reaching for supplements, check your dog's food composition — often simply switching to higher-quality food with flaxseed brings noticeable improvement within 4–6 weeks.
Can stress cause hair loss in dogs?
Yes — chronic stress disrupts hormonal balance and directly affects the hair growth cycle. Increased shedding after a stressful event is common and usually subsides on its own once the situation stabilises.
Can hair loss in dogs be a symptom of illness?
Yes — thyroid insufficiency, Cushing's disease, allergies, fungal infections and parasites are the most common disease-related causes of excessive hair loss. With bald patches or other accompanying symptoms, a visit to your veterinary surgeon is necessary.
Does frequent bathing cause hair loss in dogs?
Bathing too frequently destroys the skin's natural lipid barrier and weakens hair follicles. Your dog should be bathed no more than every 4–6 weeks, using shampoo designed for dogs.
Can food cause hair loss in dogs?
Yes — food low in animal protein, fatty acids and zinc directly worsens coat condition. Switching to food with high meat content often brings noticeable improvement within 4–8 weeks.

Summary

Hair loss in dogs is a natural process but only when it occurs evenly, seasonally and without accompanying skin symptoms. In other cases it is a signal that something needs attention diet, parasites, allergies or illness requiring veterinary diagnosis.
Start with the basics: check your dog's food composition, introduce regular grooming and parasite prevention. If despite this the problem does not improve within 4–6 weeks a visit to your veterinary surgeon is necessary.