Developed a rash? cant tell what is causing it?

i was taking an antidepressant for a week when it started. the rash is ot hives, the bumps are small but have gotten smaller and the rash is spreading to othe parts of my body, started out on my upper body, the bumps arent very pronounced and only some of them are slightly red. i dont think its dry skin it started after i used skin lotions from bath and body works and perfumed lotions that i have always used and didnt break out from. what could be causing it the only new detergent i used was oxiclean, but i didnt use it on all of my clothes, and on none of my towels, and when i got the rash the shirt i was wearing had not been washed with oxiclean.