Why Is My Dog's Hair Falling Out in Circles?

Circular patches of hair loss can occur on a dog for several different reasons. Owners of dogs who experience this condition should seek out a veterinarian's care, as some causes of circular hair loss can be contagious.

  1. Alopecia

    • According to the PetMD website, some dogs may suffer from a condition known as canine alopecia (hair loss.) This can cause circular bald spots that may be accompanied by redness, inflammation or crusty skin.

    Ringworm

    • Ringworm, a highly contagious fungal infection, can result in loss of circular patches of hair on a dog. Ringworm can be spread through direct contact with infected animals, contaminated items such as grooming equipment or contaminated places where the infected animal has been, according to the Pet Education website.

    Fleas

    • Dr. Rosanna Marsalla on the Pet Place website notes that dogs who are allergic to flea bites will suffer from circular patches of hair loss, which can turn into larger patches of hair loss if the flea situation is not remedied.

    Solution

    • Since there are different causes for circular patches of hair loss in a dog, it is important that the dog is seen by a veterinarian. A veterinarian can recommend the proper course of treatment for the affected dog.