This is what we usually advise for mange. I like to use both the shampoo and Derma-IonX to give relief. I would bathe with Defendex shampoo once or twice weekly for 4-6 weeks or a couple of weeks past having a negative skin scraping. Once a week can be sufficient, but if the pet starts scratching more after several days the owner can give another bath. Since you don't have a positive skin scraping you might be dealing with very bad allergies which is fairly common among pitbulls. It is OK to use the shampoo even if there are no mites since it doesn't contain toxic chemicals. The essential oils in it are beneficial in other ways.
I would also use Derma-IonX to heal and soothe the skin as well as rebuilding the immune system. Giving Canine probiotics, vitamin C, and Omega 3,6,9 will all help in that goal. Derma-IonX also helps the body to better utilize the supplements for faster results. I would start with a 1/2 dose of Derma-IonX twice daily on the food. I would also recommend a fish or turkey based food, not chicken or lamb since these are considered to be cooling in Chinese food therapy. Only use the one that is not a known allergen to your dog. It is also good to feed grain free.
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