Demodex indections can be severe and painful so it is good that you are reaching out for more information. I have had some very successful experience treating these conditions and while it does take time, you should not be seeing a worsening of the condition. Amitraz is not often used, I certainly have never used it. Instead I had my patients on a regular regimen of oral ivermectin, omega fatty acids (to help stimulate the skins immune system), sometimes antibiotics, and regular shampooing. Ivermectin is "off-label" as it is meant for large animal use but has been used safely in millions of dogs I gather. I believe some of the more current topical heartworm medications (revolution, advantage-multi) also have efficacy against Demodex however ivermectin is the time tested and true product.
She has been scratching her feet area since pup and the vet just brushed it off as food allergy and gave her steroids. I understand that steroids actually suppresses the immune system, so the immunity could not fight off the demodex so it escalated to this level after so many years.
I have been feeding her multi-vitamins and omega fatty acids but it doesn't seem to help. I hope its not an underlying problem like liver malfunction.
Ivermectin is not approved by the FDA in my country so I have to seek advice on the prescription of the drug from the local vet.
She will be visiting the vet again next tuesday, I hope to hear some good news or at least some possible and effective cure.
Thanks for the reply.