I Started With Blisters On My Right Arm That Resembled

I started with blisters on my right arm that resembled poison ivy. That seemed to spread rapidly to my arms and torso, and a few spots on my legs. I have had 2 rounds of antibiotics and steroids. Now the blisters have turned to large welts and itch. Those on my stomach and breast (right side only) are very painful. My doctors are treating me for reaction to medicine. The only new medicine I have been subscribed is Esbriet, which I have been on since May. Could I also have shingles.