skin issue with my cat

Question
I have an American shorthair, spayed female about 2yrs old. Her days are CONSUMED with constant licking and chewing on herself. Mostly at the base of her tail and around her back end. Her neck also has "wart-like" bumps that seem to have scabs on them, but come off easily with tufts of hair when she scratches with her back feet. She is being fed wheat free dry food and purified water. I have recently started adding essential oils to her food too. The frustrating thing is, I also have a male shorthair not much older than her and he has no skin issues at all! I am at my wits end with her cause my heart goes out to her constant misery!! Please help.

Answer
YOu are describing something in cats known as "miliary dermatitis."  THis is how cat show skin allergies.  Ask your vet to try a shot of DEpoMEdrol to see if it helps the cat.  Also have the cat checked for ear mites as there is a skin reaction to migrating ear mites in cats that can mimic miliary dermatitis.