What Causes Itchy Red Spots On Back And Chest?

I HAVE RED SPOTS ON MY BACK AND CHEST....A COUPLE ON UPPER ARMS. SEEM TO BE SPREADING SOME. ITCH. DRY. ROUGH. I HAVE HAD BREAST CANCER TWICE. LEFT BREAT REMOVED. TAKE SYNTHROID,
PINDOLE, LIPTOR AND RAMPIRIL MEDS TOGETHER WITH VITAMINS. FIRST TWO WEEKS IN JANUARY WERE IN PALM DESERT. ATE DINNER OUT MOSTLY. WOULD MITES CAUSE SUCH AN IRITATION.