top of page

Hair Loss in Dogs and Cats

There are several reasons why cats and dogs can lose their hair.  The first thing to look at concerns if they are itchy or not.  Losing hair because the skin is inflamed has different causes than non-itchy hair loss.  Licking, biting, scratching, or rubbing the skin are all considered itching.

The cat or dog is itchy and losing hair
  • Parasites

  • Bacterial infection (most commonly staph)

  • Fungal infection (yeast or ringworm)

  • The pet is barbering the hair- which means they are chewing and pulling out their hair as a way to itch the skin.

  • Allergies to food, fleas, or environmental allergens like dust mites or pollens.

  • Autoimmune diseases like pemphigus foliaceus

The dog or cat is not itchy and losing hair
  • Hypothyroidism (thyroid level too low) in dogs

  • Hyperadrenocorticism (cortisol levels too high, also called Cushing’s) in dogs

  • Demodicosis- a type of hair follicle parasite

  • Bacterial infection (most commonly staph)

  • Fungal infection like ringworm in cats

  • Color dilute alopecia- seen in blue and silver colored animals

  • Congenital or hereditary- certain breeds like dachshunds

  • Autoimmune disease

At your appointment, we will take samples from the surface of the skin and determine if infections or parasites are playing a role.  Infections of the skin are often secondary to an underlying process like allergies, especially when the pet is itchy.  We will work with you to diagnose the underlying cause and discuss treatments to prevent the problem from returning.


This dog has hair loss due to yeast overgrowth secondary to allergies.


This dog has hair loss due to a hormonal disease called Cushing's.

bottom of page