Have you taked to an Allergist or an Immunologist? if u havent i would highly recomend it! the allergist might be able to help you find triggers, and either could get a lot of blood work on ur immune system and test it, to see if that is the problem! if nothing else the immunologist could give u more info on the immune suppresants... but i would not just start taking them without talking to a specialist, or at least getting some testing, or blood work! if there is something wrong with ur immune system you could really hurt it by taking something that could make it worse... so i would definately see some specialists, or at the very least a 2nd opinion from another derm.
Hope something in here helped, and i hope u get whatever this is straightened out!
"In God's hands, in God's time."
"The scourge of life, and death's extreme disgrace, the smoke of hell, that monster called Pain."