How Can itchy Pimples On The Lower Back And Chest Be Treated?

since nov .2016. i have on back of head,rash.starts out looking like pimples/acme;very itchy. it has spread to lower back and chest area as a rash and covers a large area. have seen a dermatologist. tried 2 different antibiotics, shampoos, topical lotion, over the counter shampoos for lice,dry itchy scalp, anti itch lotion,acme over the counter medicines. dr. took sample and sent in. called back with no solutions. rash makes my skin feel like leather to touch. continues to itch 24 hours. shampoo my hair daily. when it shows up as a pimple, it takes 3 weeks to disappear, red in color. my back of head continues to get more and very itchy. i work at hotel, with a lot of people from overseas. wash my hands continually. take the following medicines: atenolol 50, lisinopril 20mg, simvastatin 40 mg., bayer low dose 81mg. taken since my double by-pass heart surgery, 10/2006. over the counter medicines: nature way beet root 500 mg, krill oil 1000mg, probio slim. no fried foods, red meat once a week, fish. bake all foods. watch all the foods that eaten, juice daily. low fat milk,breads, cheeses, no snacks