I thought i had a allergic reaction to something because.my legs got this rash well two types of rashes along with swelling. one of the rashes looked like hives, the other one was. adeep dark purple color almost the way a birth mark lokks you know a sttwberry patch, but i started taking allergy meds and the rash.went awaybut the swelling stayed and. it seems to be moving up my legthe purple stuff it starts out like pock marks little dots then it suddenly grows and then swells