Dogs and puppies
Puppy mange, also known as demodectic mange, is caused by a skin parasite called Demodex. Demodex is a type of mite.
The Demodex mite is ubiquitous, and in most dogs it causes no symptoms. However, if an individual’s immune system experiences irregularities, the mite may trigger hair loss or other dermatologic problems. Dermatologic problems from Demodex are most common in dogs less than two years of age. Therefore, the syndrome sometimes is called puppy mange.
- The most common symptom of puppy mange is hair loss over small patches of skin. Hair loss most frequently occurs around the eyes, on the muzzle, or on the face. However, puppy mange can lead to small bald spots anywhere on the body.
- Generalized hair loss over large portions of the body can be a sign of a less common, but more serious, form of demodectic mange.
- Often, the skin in the areas of hair loss appears normal and does not itch. However, in some instances the affected areas may be red, thickened, irritated, itchy, or malodorous.
Risk Factors and Prevention
Although Demodex mites are technically contagious, puppy mange generally does not spread from dog to dog. Almost every dog is exposed to the mite early in life, and therefore Demodex are present on almost every dog. Dogs that show symptoms do so because their immune systems do not respond to the mites appropriately.
- Age is the leading risk factor for puppy mange. Dogs less than two years of age may experience hair loss and other symptoms as the immune system matures.
- Purebred dogs are more likely than mixed breed dogs to show signs of puppy mange.
- Dogs with underlying systemic diseases such as diabetes are more likely to develop demodectic mange, especially as adults.
Dogs with hair loss in small patches usually do not suffer major complications from puppy mange. However, affected areas of the skin may become irritated or infected. Dogs with patchy hair loss may have bald spots for many months before the problem resolves.
Dogs with generalized hair loss on large portions of their body can suffer severe skin infections and dermatologic problems.
The most common complication of puppy mange is owner frustration. This occurs because the syndrome, as mentioned above, can take many months to resolve.
Puppy mange is commonly diagnosed by identifying the mites in samples obtained by abrading affected areas of the skin. This test is called skin scraping. A microscope is necessary to identify the mites.
In some cases, a presumptive diagnosis of demodicosis may be made based on a dog’s age and the presence of characteristic patches of hair loss.
In some cases, tests such as cultures or microscopic analysis of skin fragments are performed to ensure that other causes of hair loss such as ringworm are not contributing to the syndrome.
Dogs with small areas of localized hair loss generally do not need aggressive treatment. Sometimes the symptoms are monitored and allowed to resolve spontaneously as the immune system matures. Other times, a topical medication is applied to the area to speed the healing process. The most commonly used topical medication is called Goodwinol Cream®.
A high quality diet and the opportunity for adequate activity and rest will help to strengthen the immune system and speed the resolution of symptoms. Pets with puppy mange also should receive appropriate flea control.
Dogs with concurrent diseases such as diabetes should undergo appropriate treatment for the disease. This is more likely to be a consideration when Demodex affects dogs over two years of age.
Dogs with generalized hair loss over large portions of their bodies may be treated with a medicine called Mitaban®. The medicine is applied over the entire body (often in the form of a shampoo). Mitaban® must be used with caution. It is potentially toxic to dogs and people.
Less commonly used treatments for puppy mange include ivermectin, lime-sulfur dips, and daily administration of milbemycin (Interceptor®).
Repeated skin scrapings at regular intervals may be used to monitor a dog’s response to treatment. Dogs with mild cases may simply be monitored for resolution of hair loss, without further skin scrapings.
When dogs are treated for puppy mange, their hair loss often appears to worsen for a brief period before improvement occurs.
Puppy mange can take several months to resolve. It is not uncommon for dogs to experience relapses of hair loss until their immune systems mature. Many individuals develop new areas of hair loss as old areas resolve. Although these features of the syndrome may be frustrating for the dog’s owner, they usually do not harm the dog.
As mentioned above, although Demodex technically is contagious, it does not behave in a contagious fashion. The symptoms of the disease are closely linked to the response of the dog’s immune system.
Cats are rarely affected by Demodex.
Copyright © Eric Barchas, DVM All rights reserved.
The contents of this page are provided for general informational purposes only. Under no circumstances should this page be substituted for professional consultation with a veterinarian.