Dr. Bammel and Andie

We got a puppy for my children at Christmas. A couple of weeks ago he started having bald patches on his head and shoulder. The vet diagnosed him with “demodex” mange and we got him dipped. His skin does not look any better, maybe even worse. What now?

– Jan

Dear Jan,

Treatment of demodex is not a “one-stop-cure” kind of disease. Treating it takes some time. Demodectic mange is caused by the microscopic mite Demodex canis, which burrows down into the hair follicle to live. The mite scratches up the inside of the hair follicle and causes the hair to fall out leaving a bald spot that is usually slightly scaly and red.

Dogs can have a small localized infection just in one area, usually on the face or on the front legs, or they can have a generalized infection with large patches over most of the body.

Demodectic mange is NOT contagious to you or other pets, unlike sarcoptic mange which is contagious to other animals and people.

Oddly enough, it appears that most dogs actually have a few of these demodex mites on their skin, but the average dog’s immune system doesn’t allow the mite to cause an infection. No one knows why some dogs develop the mange, but it is thought that some animals have a genetically weaker immune system to fight the demodex mite. Stress and rapid growth can also contribute to weakening the immune system.

The demodex mite lives deep in the hair follicle, so treatment can be tough sometimes. Treatment options are a special pesticide dip once a week or medications taken by mouth every day. Both treatments must be done until two skin tests are negative for mites.

Dips can be difficult to do on wiggling puppies with mange on the face because the dip can be harmful to the eyes. The pesticide dip can also make the puppies feel really sick for a couple of days. I tell clients to expect three to six dips, or more.

The daily oral (by mouth) medications milbemycin or ivermectin must be given for 60 to 90 days. There are some pure-bred and mix-breed dogs that can get deathly sick from taking the medications, so some vets will now do a special “MDR1 test” to make sure a dog can safely take the medication. Also, it is easy to overdose and kill a puppy with these drugs, so caution must be taken when deciding on an amount to give.

I also typically recommend some homeopathic immune support items and good nutrition to help the immune system fight the demodex mite. Treatment is generally successful unless a dog owner is non-compliant with veterinary recommendations.

Every case of demodex mange is different, but getting rid of this infection will not be done in a week. Go back for follow up dips as directed and ask your vet if you have any other concerns.

Good luck!

– Dr. Bammel and Andie

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