Suggest Remedy For Rashes Appearing On The Back & Neck

Hello! i need your help for my rashes at my back and around my neck becoming black sometimes red. i had ANA test 3 years ago and it was above normal level. i consulted a rheumatologist , he said a dermatomyositis but no enough diagnostic done to me, he based only with my skin rashes.my rashes increased until my scalp it seems my scalp become thick. after i was diagnosed as my rheumatogist said that it is dermatomyositis he prescibed me prednisolone 5mg, and plaquenil. i took for 1 and half month i stop gradually because i was afraid of prednisilone. please help me if my rashes is really a dermatomyositis. thank you.