Hair Falling Out in Dogs

Why is my dog hair falling out?

What is Hair Falling Out?

Many different diseases and conditions can result in hair loss in your dog. Your dog losing hair can be normal, for example when shedding as the temperature warms, or can be the sign of a health concern requiring medical attention. The following are the more common reasons for your dog’s hair falling out:

  • Allergic and irritant contact dermatitis
  • Atopy (allergic inhalant dermatitis)
  • Callus
  • Cushing’s disease
  • Demodectic mange
  • Folliculitis
  • Food allergies
  • Pregnancy and nursing
  • Hypothyroidism
  • Ringworm
  • Sarcoptic mange
  • Sebhorrea
  • Tail gland hyperplasia

Should hair loss be occurring outside of seasonal shedding, you will want to schedule an examination with your veterinarian to determine what is leading to your dog losing her hair.

Why Hair Falling Out Occurs in Dogs

Your dog’s hair may be falling out due to:

Allergic and Irritant Contact Dermatitis

This is an allergic reaction that comes after your dog is exposed to any of the following: antibiotics on her skin, metals like nickel, materials like rubber, wool and plastic, and chemicals like dyes or carpet cleaners. Typically, more than one exposure will be required. 


Atopy is an allergic reaction that can occur if your dog inhales pollen, house dust mites or mold. Redness, leathery skin, and hair loss are just three of many symptoms associated with atopy.


This condition is the result of ongoing pressure, particularly in larger breeds of dogs. With this condition you may notice thickened, hairless, raised areas over bony pressure points like elbows. In some cases, secondary infections are present.

Cushing’s Disease

This condition is due to an increase in corticosteroids in your dog’s body. This can be the result of her body increasing the production of them or may be a side effect of her taking a high dose or long term corticosteroid.

Demodectic Mange

Should your dog be infected with the Demodex mite she can experience demodectic mange. The infection can occur when your dog’s immune system is weakened. In addition to hair loss, you may observe scaliness, redness, ulcers and darkening of your dog’s skin. Itching may be present in some cases. 


This occurs when the hair follicles become infected, in many cases with staph bacteria. Symptoms are typically seen on your dog’s skin where less hair is present.

Food Allergies

Your dog can experience an allergy to something in her diet. Symptoms in addition to her losing her hair include her licking her feet, ear inflammation, itching, redness and in some cases, infection or hot spots.

Pregnancy and Nursing

Excessive shedding can occur in your dog should she be pregnant or nursing; hormone changes contribute to this condition.


Hypothyroidism is a condition where there is a decrease in your dog’s production of the thyroid hormone. This is the most common hormonal disease in dogs that impacts their skin.


Ringworm is an infection with several types of fungus. Should your dog have ringworm you may observe scaliness, crusty areas, pustules, some itching and hair loss.

Sarcoptic Mange

Sarcoptic mange is the result of an infection with the Sarcoptes mite. You will observe significant itching, self-trauma, papules, crusts and scales as well as hair loss.


The condition can be inherited or the result of another condition (allergies or hypothyroidism for example). Odor, oiliness and inflammation are often seen with seborrhea.

Tail Gland Hyperplasia

Your dog has a sebaceous gland on the top of her tail near its base. Should the gland become enlarged, it is called tail gland hyperplasia. This is found in unneutered dogs as well as a secondary condition to another disease (for example hypothyroidism).

What to do if your Dog is Hair Falling Out

Should you observe your dog losing a lot of hair outside of the usual seasonal shedding, you will want to have her examined by your veterinarian, as hair loss may be due to an underlying health condition. Your veterinarian will ask you for information regarding how long the hair loss has been occurring, whether your dog has appeared to be itching, as well as whether there are any other symptoms you have noticed and when you first noticed them. A physical examination will be conducted so that your veterinarian can view the areas where your dog has been losing hair and the skin where the hair has been lost.

Depending on what is seen during the physical examination, additional testing may be suggested. This can include a patch test, blood testing, urinalysis, testing of the function of her adrenal glands, skin scraping and microscopic examination, and a biopsy. If a food allergy is suspected, an elimination diet will be recommended.

Because hair loss is a symptom for many different possible conditions and diseases, it can take time for your veterinarian to make a diagnosis.

Prevention of Hair Falling Out

Feeding your dog a healthy diet that meets her nutritional requirements is important to help with the function of her immune system so that her body is best prepared to fight causes of infections. Ensuring that she receives regular exercise is also important for her overall health.

It is a good idea to take your dog for annual check-ups with your veterinarian to ensure that any potential health issues are caught early and can be treated right away before they lead to more significant issues.

Cost of Hair Falling Out

The cost of your dog’s hair falling out will be dependent upon the condition that is causing it to occur. Her hair may fall out as a result of shedding, which will not require treatment. If your dog is losing hair as a result of ringworm, for example, the average cost of treatment is $450.  Should the hair loss be the result of Cushing’s disease, the average cost of treatment is $2,000. In hypothyroidism, the average cost is $1300. All costs will vary based on the location where treatment is obtained.

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Hair Falling Out Questions and Advice from Veterinary Professionals


Akita Pointer




12 Years


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My pet has the following symptoms:
Hair Loss
Dry Cough
Dry Patches
Crusty Scabs
Circluar Patches
He’s been getting these circular patches lately and we thought it was ringworm but since there was no risen skin around it and it wasn’t going away with fungal cream, we thought it was just old age or stress because he lost hair on his tail and rear when his pack died. At first they were only on his stomach but now it’s on his back. Please respond soon.

Dec. 13, 2017

0 Recommendations

There are various causes for a loss of hair which may include stress, seasonal allergies, hormonal conditions (Cushing’s), parasites (don’t always present with itching) among other conditions. I would get Demon checked over by his Veterinarian to diagnose the specific cause of the hair loss so that an effective treatment may be given (we don’t want to be treating a best guess); your Veterinarian may take a skin scraping and blood tests to help make a diagnosis. Regards Dr Callum Turner DVM

Dec. 13, 2017

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