Demodex in Dogs

Generally, once your dog has had an infestation of demodex and the mites have been completely eliminated, they do not become re-infested with the mites. This is because your dog’s immune system is now able to recognize and eliminate any new demodex mites. Some dogs that have a weak immune system will not be able to eliminate the mites without medical intervention.

Demodex, also known as demodectic mange, in dogs is a mite infestation on your dog’s skin. The mites are tiny, eight legged, cigar shaped, and feed in the hair follicles and oil glands of the skin. Most cases of demodex are self-limiting, meaning your dog is able to stop the growth and reproduction of the demodex mites and will also repair the damage that was done by the mites.

When Demodex first appears, it may just look like a small spot of hair loss, possibly from rubbing the area. However, if you notice any crusting on the skin or the hair loss spreads contact your veterinarian for an appointment. Symptoms of Demodex to look for include:

• Hair loss in patches
  
• Rubbing their face or head
• Redness or inflammation of the skin
• Excessive oil on the skin
  
• Crusting on the skin
• Paws that are swelling
  

Types

Demodex has three distinct varieties.

Localized

This type of demodex will affect only a few parts of the body, usually the face. It will appear as just a small lesion around the face and is commonly seen in puppies. Most cases of localized demodex will resolve without any treatments as the puppies immune systems mature.

Generalized

This type of demodex will affect larger areas of skin or possibly the entire body. Generalized demodex will many times cause secondary bacterial infections. These bacterial infections will cause intense itching and a foul odor. It can be very difficult to fully eliminate all the mites.

Demodectic Pododermatitis 

This type of demodex is located on the feet only. It causes secondary bacterial infections that are located between the pads and the toes. This type is the most difficult to fully cure.

Demodex is caused by the Demodex canis, which is a parasite or mite that lives in the hair follicles of dogs. All dogs have these mites living on their skin but will not have a reaction to these mites unless their immune system is deficient. 

Demodex is most common in puppies and dogs that have immature immune systems. The mites will multiply uncontrollably when your dog’s immune system is immature or weak and unable to properly dispose of the excessive mites. Most adult dogs will be able to fight off the excessive mites without needing medical intervention. Older dogs may also show symptoms of demodex as their immune systems begin to decline and with age.

Your veterinarian will begin by taking a complete medical history on your dog. They will also ask you about any changes in diet or environment. Then, your veterinarian will complete a full physical examination on your dog, paying close attention to any bald spots or noticeable lesions.

Your veterinarian will do a complete blood count and will also do a skin scraping of an affected area. The skin scraping will be placed under a microscope and your veterinarian will look for mites. Demodex canis mites are fairly easy to spot under the microscope. 

If your dog is a mature dog, your veterinarian may also search for the reason the Demodex canis mites were able to multiply uncontrollably. There is usually an underlying cause that is suppressing the immune system and sometimes it is extremely difficult to find what that cause is.

Once your veterinarian has diagnosed demodex they will begin treatments to get rid of the overgrowth of mites. Anti-mite creams can be used as well as anti-inflammatory creams and corticosteroid creams. Your veterinarian may also recommend using benzoyl peroxide on larger areas. Your veterinarian will probably trim the hair around the affected areas. This will allow the prescribed creams to work more effectively on the affected areas. 

Some cases of demodex may require the use of anti-parasitic medications. Your veterinarian will prescribe the medications they feel will work best on your dog. Antibiotics may also be used in cases where bacterial infections from the demodex have occurred.

Most cases of demodex are treatable. Dogs that are suffering from a weak or suppressed immune system will be much more susceptible to other diseases and conditions as well as relapses of demodex. Dogs that have immature immune systems, such as puppies, will generally recover from demodex and will not have a relapse. 

Speak with your veterinarian regarding your dog’s prognosis. Dogs that have weak or suppressed immune systems should not be used for breeding. Puppies who have developed a case of demodex can still be bred when they are older as long as the demodex does not recur.

A demodex infestation can be expensive to treat. To avoid high vet care expenses, secure pet health insurance today. The sooner you insure your pet, the more protection you’ll have from unexpected vet costs.