I Have Had An Itchy Rash And Hives/ Red Circular

i have had an itchy rash and hives/ red circular rings showing up everywhere for over two weeks. began with quarter sized welts on scalp and neck. was told i had fleas. two weeks later the welts turned into red rings about a quarter each on my face neck chest and back. this doc told me it was ringworm. am on turbafine and a potent antihistamine. after five days im still getting more new areas and they have effectivly covered all of my body but my soles and palms. they tend to come and go. lasting about a whole day. hard to say but some of them may have been around for awhile. cant tell with all of them so abundant. the second doc did have me stop my phentermine cause it was the only "new" drug i had been taking. i had been taking it for 6 weeks at that point. it seems to be lessening somewhat but there are clearly new ones daily. any suggestions? i really want an answer and a third trip to the doc is getting expensive if there dosent seem to be concrete proof of what is going on.