my cousin and i were cleaning out backyard shed. that evening top of both of my feet started itching. thinking maybe poison oak etc. inquired of cousin if they were experiencing same. No.  then top of both of my feet began to have several big blisters and doctor had to treat but it made area on foot raw to under layer of skin. top layer was pulled off.  both feet healed well. could see no scars.  now this summer, feet are breaking out and blistering again just like before.  dr only prescribe topical ointment.