My father is being treated for herpers zoster.he had blisters around his right back one month back. he is still having pain and itching around the back area although the blisters are gone now. Also, from a few days, he is having pain around lower back as well with some blisters/bumps. Wanted to know if blisters/bumps still occur even after medication. he is still taking pregaba m for pain. still he cant sleep due to pain.. the pain is also causing strain near stomach..wanted to know if herpea zoster can spread internally as well or cause pain in internal organs? also, any suggestion for the pain and itching?