What Causes Itching And Redness On Neck And Upper Chest?

i HAVE HAD ITCHING SENSITIVE SKIN FOR ALMOST 10 MOUNTHS. i HAVE SEED MY FAMILY DOCTOR AND AFTER TAKING CREAMS AND PILLS THAT DID NOT IMPROVE MY PROBLEM SHE SENT TO A DERMOTOLOGIST. I have been seeing him for 4 weeks and he has tried different lotions and pills but I still have this overly sensitve itchting skin and redness all along my neck AND UPPER CHEST. THEY WANT TO DO A SKIN BIOPSY. SHOULD I DO THAT OR TRY TO FIGURE OUT WHAT MAY BE CAUSING THISTHROUGH GENERAL PRACTIONER DOCTOR?