If your dog’s hair starts falling out suddenly, it can be an alarming and worrying sight. But, as distressing as it can seem, hair loss in dogs is reasonably common and usually treatable — depending on the underlying cause.

Dogs of any age or breed can suffer from hair loss, at any stage of their lifetime. Hair loss in dogs and bald spots in dogs can be caused by a range of factors — from moderate issues to more serious health problems — and in this guide, we’ll look at some of those typical conditions. We’ll also cover likely treatment if your dog is losing hair in patches.

It’s important that you don’t mistake a dog’s hair falling out with shedding, which is a natural process and occurs during the year. Shedding is the way that dogs lose old hair to replace with a newer, healthier coat.

This may sound like a question with an obvious answer, but the symptoms of hair loss and alopecia in dogs can be wide-ranging – from noticeable bald patches on a dog to a dog’s hair falling out in larger quantities. Some of these symptoms can be quite subtle, so it’s not always clear that your dog could be living with alopecia.

Commons symptoms of hair loss and alopecia in dogs can include:

There are other symptoms of alopecia in dogs, too, that may not seem so physically obvious compared to noticeable skin issues.

These can include:

If you notice any or some of these symptoms, consult your veterinarian. Your dog may be suffering with alopecia — or there could be another underlying health issue. Either way, it’s wise to speak to a professional.

So, what’s causing these bald patches on your dog? There are, actually, a large range of causes so it’s not simply a process of understanding immediately why your dog’s hair is falling out. That is for a vet to understand and explain.

Possible causes of alopecia in dogs include:

Unfortunately, some breeds of dog are more prone to experiencing alopecia than others. Hereditary alopecia is thought to particularly affect a number of breeds, including:

These breeds of dogs may also have a condition known as Alopecia X.

With such a wide range of potential causes for hair loss in dogs, don’t guess at the issue: a visit to the vet is imperative.

Your veterinarian will examine your dog to determine the underlying cause and therefore be able to recommend a course of treatment. Diagnosis is based on the onset of signs, pattern of hair loss, the skin’s condition around the area of hair loss, and whether your dog is showing signs of discomfort — either in pain or by itching.

The process of diagnosing alopecia in dogs may include the following:

Pattern of hair loss in dogs

Generalized hair loss in dogs could be a sign of mange or bacterial infection. Patches of hair loss could indicate conditions like ringworm, bacterial infection, mites, or mange. Hair loss in the rump and tail base area is often due to a flea allergy.

Hair loss from the paws and face is sometimes environmental allergies (atopy). Symmetrical hair loss could be a sign of adrenal gland disorder, thyroid disorder, or abnormal sex hormone levels (endocrine disorders).

Blood profile

Blood testing will help to diagnose certain immune system conditions, hormone abnormalities, thyroid disorders, Cushing’s disease, and Diabetes mellitus.

Biopsy

If skin cancer or a tumor is suspected, or in persistent unresponsive skin lesions, the veterinarian may want to send a sample of the affected area to the laboratory to determine diagnosis and treatment.

Skin impression smears

Pressing a microscopic slide on the affected area and analyzing it can show the presence of bacteria, yeast, or inflammatory cells.

Skin scraping

Scraping the skin gently with a blade to gather hair follicles onto a slide can help detect the presence of mange mites.

Luminescence
Some ringworm species will glow a fluorescent green-yellow under ultraviolet light.

Allergen elimination trials

Feeding a hypoallergenic diet, treating fleas, or eliminating the use of certain shampoos or drugs may reveal an allergy to a certain food.  

Allergy testing

Skin and/or blood tests can narrow down the list of potential environmental allergens.

When your vet has successfully diagnosed the cause for your dog losing its hair in patches, treatment can begin. A variety of treatments available – depending on the cause of your dog losing hair.

Typical treatment options can include:

If hair loss in dogs is due to chemotherapy treatment, you could expect this to clear when chemotherapy sessions are completed. However, hair loss may be permanent when caused by genetics, scarring, callouses or pressure sores.

Most hair loss, when treated properly, will resolve — but recurrent skin conditions may require ongoing treatment.

Your dog should, all being well, recover from hair loss but depending on the cause and severity may need to be treated more than once.

Always administer treatment according to the veterinarian’s instructions. Follow-up appointments may be necessary to ensure the problem is improving and that any infection is clearing up.

As a pet parent, you have a job to do: to monitor your pet’s skin and hair regrowth and communicate any changes or concerns to the veterinarian so they can adjust treatment accordingly.

Hair loss can be expensive to treat. If you aren’t already covered, you should start searching for pet insurance today, which can help to support the cost of treatment.

Compare insurance plans from leading companies like PetPlan and Trupanion and find the perfect plan for your pet in just a few clicks!

Curious about which health plan is right for your dog? Read our breakdown of the best pet insurance plans here.