Are Methotrekate And Celcept Effective For Recurrent Skin Rashes?

I have had these skin rashes for over a year.
All three dermatologists have given topical steriods, injected steriods and now predisone.
The rashes went away after taking predisnone for ave2 mos. but now I have stopped taking and the rashes are coming back.

Doctor wants me to choose between Methotrekate and Celcept?
Do you think these will help?
Is the doctor on the right track?

Thanks, Gerry