Spotty Hair Loss in Dogs

Keeping an eye on a dog's coat does more than tell an owner when to brush it--it also helps measure a dog's health. A healthy dog has a healthy coat. A dog that is experiencing spotty hair loss should be checked for a health problem.

  1. Spotty Hair Loss

    • Spotty hair loss in dogs can be caused by a fungal infection or by a skin infestation of tiny mites. Ringworm is a highly contagious fungal infection found in the skin of mammals. Tiny mites that infest a dog's skin, especially its hair follicles, can cause a skin condition called mange. Mange is classified as either demodectic or sarcoptic, and both types can cause spots of hair loss.

    Symptoms

    • A dog with ringworm will lose hair in round spots, usually on its paws and forelimbs and its head and ears. Within these bald spots, an owner might spot red skin lesions, according to the ASPCA. Mange causes patchy hair loss, leading to a moth-eaten appearance especially around a dog's eyes and ears. The spots where a dog has lost hair could be itchy, leading to increased scratching.

    Diagnosis

    • A veterinarian can diagnose ringworm by examining the dog's hairs under a microscope or by taking a culture of the skin in the affected area to examine more closely. Because two different mites can cause mange, a veterinarian will need to take a skin scraping from the infected dog. She can then view the scraping under a microscope and determine which mange is causing the problem.

    Treatment

    • Ringworm is usually treated with topical ointments. In more severe cases, oral antifungal medication could be needed to completely clear the infection. Mange is treated with medicated shampoos and dips that will kill the mites. Medication like ivermectin can be administered by injection or orally. It will linger in a dog's bloodstream and prevent reinfestation by mites, according to "The Complete Healthy Dog Handbook."

    Considerations

    • With both ringworm and mange, spotty hair loss will stop as soon as treatment begins. Once the infections are cleared, a dog's hair will begin to grow back. Ringworm can be transmitted from dogs to humans, so it is important to seek treatment for it right away. When treating a dog for mange, it is important to completely clean a dog's living area to avoid the risk of mites hiding in its bedding and infecting the dog again.