Generally the rheumies use plaquenil and prednisone first.
Then they add one of the 3; Imuran, Cellcept, or MTX(methotrexate). If the first one of these they try doesn't do anything, they move along to the next. There is no rhyme or reason as to which to pick or in which order to try them, I think it's just up to the Dr what s/he prefers.
My Dr started with Imuran - it did nothing for me. No improvements, so side effects, nothing. So then we moved along to Cellcept, which turned out to be my miracle drug - basically put me in remission. Side effect was hair thinning, but since stopping Cellcept it has since come back.
Other people get great results with Imuran, or MTX... it's all just magic! Hope the Imuran works for you!
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2000DIAGNOSING LUPUS & HW's LUPUS 101
"Life is far too important to be taken seriously." - Oscar Wilde