Why is my dog shedding so much (and what to do)

"My dog is losing hair in clumps, is that normal doctor?" It's one of the most commonly asked questions in veterinary consultations. The short answer: it depends. The long answer: there are at least seven possible causes, and knowing how to distinguish them avoids unnecessary trips to the vet — or worse, missing a real problem. If you're wondering why your dog is losing its hair, this guide helps you make an initial diagnosis, know when to consult, and manage the hair storm with the right tools — like a reusable pet hair brush.

We go from the most mundane (seasonal shedding, which alone accounts for the majority of cases) to the more medical (hormonal pathologies). In the end, a quick diagnostic chart to guide you, a daily routine, and a FAQ that answers the most frequently asked questions.

First, how much hair loss is "normal"?

A dog sheds hair continuously: it's mechanical. According to the WSAVA, an adult dog renews its entire coat every 4 to 6 months. Aside from any pathology, your carpet will therefore receive hair every day.

What should raise concern is not the absolute volume (which varies greatly by breed and season), but a change: sudden increase, bald patches, or hair coming out in tufts where there wasn't any before.

Cause n°1: seasonal shedding (the most frequent culprit)

By far the most common cause. Dog shedding occurs twice a year in double-coated breeds: in spring, the winter undercoat falls out in large amounts; in autumn, a denser undercoat replaces it.

Australian Shepherd, Siberian Husky, Golden Retriever, Labrador, Bernese Mountain Dog, Border Collie, Samoyed, all northern breeds and more broadly, double-coated dogs. If you live with an Australian Shepherd in spring, you don't have a medical problem: you have an Australian Shepherd.

Three signs confirm a normal shedding: massive but even loss (no bald patches), duration of 3 to 6 weeks, and the dog otherwise in good shape (appetite, energy, healthy skin, no itching). If you check all three, breathe easy: it's just biology.

Cause n°2: breed genetics

Some breeds shed a lot of hair all year round, while others hardly shed at all. It's not a matter of "quality": it's genetic. The profiles from the Société Centrale Canine detail these traits by breed standard.

Breeds that shed a lot: Husky, German Shepherd, Australian Shepherd, Akita, Pug (yes, despite its short hair). Breeds that shed very little: Poodle, Bichon, Yorkshire, Schnauzer, Coton de Tulear. If you adopted a Husky hoping to save on hair, the battle is lost — but a good brushing routine changes everything.

Cause n°3: stress and anxiety

Less known, but very real. A stressed dog can lose hair diffusely, sometimes in just a few days. The mechanism is hormonal: cortisol disrupts the hair cycle.

Typical triggers: moving, the arrival of a baby or another animal, prolonged separation, boarding, change of routine, persistent loud noise. If the hair loss coincides with one of these events, you probably have the culprit.

Stabilize the routine (meal times, walks, bedtime), spend more time in positive activities with your dog, and consider calming supplements approved by your veterinarian if it persists. Hair loss usually stops when the cause of stress disappears.

Cause n°4: a nutritional deficiency

The coat is an excellent indicator of the quality of the diet. Low-quality kibble, poorly balanced home-cooked diets, or deficiencies are directly visible: dull, brittle hair that falls out more than usual.

Essential nutrients for the coat: omega-3 and omega-6 (fish, salmon oil, flaxseed), zinc, biotin, quality proteins. Brands like Royal Canin offer skin and coat formulas; the ideal remains a personalized recommendation from the veterinarian based on age, weight, and breed.

Cause n°5: allergies (food or environmental)

Allergies account for a significant portion of dermatology consultations. The distinctive sign: hair loss is almost always accompanied by itching (the dog scratches, nibbles, licks) and is often localized (paws, belly, ears, base of the tail).

Classic triggers: pollen, dust mites, food proteins (beef, chicken, wheat), household products. If you suspect an allergy: head to the veterinarian. Diagnosis involves skin tests or an elimination diet.

Cause n°6: parasites (fleas, mange, demodicosis, ringworm)

Very common, especially in dogs that go outside. Fleas cause itching and localized loss (base of the tail, flanks). Sarcoptic mange and demodicosis are invisible but formidable parasites. Ringworm is a fungus that creates round hairless patches.

The ANSES emphasizes the importance of an up-to-date antiparasitic protocol. Black spots (flea droppings), round patches or localized loss with itching: vet quickly. An untreated parasite quickly contaminates the entire household.

Cause #7: hormonal pathologies (hypothyroidism, Cushing's)

Less common, but it exists. Hypothyroidism (lack of thyroid hormones) and Cushing's disease (excess cortisol) cause diffuse loss, often symmetrical on the flanks, without itching. The dog may also show weight gain, lethargy, thinner skin.

Diagnosis only through blood test at the veterinarian. If the loss is symmetrical on both flanks and the dog seems tired or is gaining weight, request a hormonal dosage. When treated properly, these diseases can be managed very well over time.

Quick diagnostic table: which symptom corresponds to which cause?

This table helps you identify the most likely cause. It does not replace a consultation, but allows you to arrive at the vet with the right observations.

Main observed sign	Probable cause	Recommended action
Massive homogeneous loss, spring or autumn, dog in shape	Seasonal shedding	Daily brushing, no worries
Continuous loss all year round, breed known for this	Genetics	Appropriate brushing, skin and coat diet
Diffuse loss after a significant event (moving, etc.)	Stress	Stabilize routine, consult if it persists
Dull, brittle fur, moderate but constant loss	Nutritional deficiency	Review diet with the veterinarian
Intense itching + localized loss (paws, belly, ears)	Allergies	Essential veterinary consultation
Round hairless patches, black spots, frantic scratching	Parasites	Emergency veterinarian, antiparasitic protocol
Symmetrical loss on the flanks, lethargy, weight gain	Hormonal pathology	Blood test at the veterinarian

When to consult the veterinarian without delay

Signs that should make you schedule an appointment quickly:

• Appearance of clearly defined hairless patches
• Intense itching or compulsive scratching behavior
• Red, scabby skin that oozes or has a bad smell
• Hair loss accompanied by fatigue, loss of appetite, or weight gain
• Loss lasting more than 6 to 8 weeks outside of seasonal shedding
• Presence of visible parasites (fleas, black flea droppings)
• Puppy that suddenly loses its hair (always suspect before 6 months)

When it comes to health, we don't improvise. PURIPAW makes tools to manage hair at home, not treatments — and that's just fine.

What to do daily to manage hair loss

Once the cause is identified (or ruled out medically), you have to live with it. Good news: a simple routine massively reduces hair in the house and improves coat quality.

On the dog: brushing and feeding

Regular brushing is the number one weapon. For a double-coated dog: 5 to 10 minutes, 3 to 4 times a week during normal periods, every day during heavy shedding. The goal: to remove dead undercoat before it falls everywhere. For dogs stressed by traditional brushing, a microfiber glove that glides on like a caress is often better accepted — and it also collects hair from clothes and throws.

On the food side: a quality kibble with a good omega-3 ratio, and possibly a salmon oil supplement recommended by your veterinarian. Avoid "miracle coat" supplements bought without professional advice.

On the dog: what NOT to do

Never shave a double-coated dog in summer. This is the most common mistake and it is counterproductive. The undercoat serves as insulation: it keeps warmth in winter but also coolness in summer. When shaved, the dog suffers more from the heat, its skin is exposed to sunburn, and the coat often grows back damaged.

On surfaces: the second line of defense

Gentle power upholstery vacuum, anti-hair textile brush in accumulation areas, regular washing of covers and throws. For delicate fabrics, we have written a dedicated guide for black velvet sofas that also applies to other delicate fabrics.

FAQ: your questions about hair loss in dogs

My female dog sheds more during her heat, is that normal?

Yes. Hormonal variations related to the estrous cycle can cause a bit more shedding. If the shedding remains diffuse and your female dog is doing well, no worries. If she leaves patches, veterinary advice.

Should you shave a double-coated dog in summer to keep it cooler?

No, never. The double coat regulates temperature in both directions. If shaved, the dog suffers more and the coat grows back poorly. In summer: intensive brushing, shade, fresh water.

My puppy is shedding, is it serious?

Veterinary advice recommended. Before 6 months, sudden shedding is never trivial (parasites, nutrition, auto-immune). Gradual shedding around 4-6 months may correspond to the replacement of puppy fur with adult fur, but we still check.

Does salmon oil really improve the coat?

Yes, in most cases, provided it is of good quality, well-dosed, and used for several weeks. Dosage to be asked from the veterinarian according to weight. It is not a medical treatment: if the shedding is pathological, the oil will not be enough.

How long does seasonal shedding last?

Between 3 and 6 weeks on average, depending on the breed and environment (an indoor dog heated all year may sometimes have a more extended shedding period). Beyond 8 weeks of massive shedding, talk to the vet.

In summary: how to know why your dog is shedding

Seven possible causes, from the most trivial to the most medical. In most cases, the excessive shedding of the dog is explained by seasonal shedding or breed genetics — nothing pathological, just biology to manage with a good routine. In a minority of cases, it is a sign of a health problem that requires a vet's attention. For anything related to health, the right reflex is: make an appointment.

For the rest — hair on the couch, in the car, on your black clothes — we have what you need. It's our story at PURIPAW: simple and durable tools to live peacefully with the animals we love.

— The PURIPAW team 🐾