I Work In The Heat And Sun All Day In

i work in the heat and sun all day in arizona and over the past month i have developed a rash in my groin and all over my body. the one in my groin looks like ringworm , but antifunal medicine has not helped. i also went to my dermatologist and they said i had filiculitous. i took the medicine and it went away, but has come back even worse, i have tried coritzone, poision ivy scrub, allergy pills, etc. most of my body has small red bumps and itch, and then my groin has a rash looks like ringworm and itches and i have small circular rashes about 5 of them on my arms and legs. any ideas what it might be????? i am 48 years old and work outdoors.