Suggest Treatment For Rash On Knees And Elbows

hello, i know there is alot of flu going around in the uk at the moment, but what i am dealing with at the moment seems to be worse than any flu i'v delt with before i have the normal caughing, sneezing, acking, weekness but my weekness is to the point there i cant walk without going dizzy, tierdness, iv got sickness and diorea, headace, i cant explain how week i am i can feel my heart beat, and now i'v noticed iv come out with a rash type on my knees and elbows.