My boyfriend is on suboxone. I questioned him on why he was on it, he said that it was for depression.?

Would a doctor prescribe this medicine for depression or just for withdrawl symptoms? I was told also that only a doctor specially licensed in drug treatment can prescribe this drug. Does anyone know any thing about this drug and is uses?

: http://alcoholdrugstreatment.info/my-boyfriend-is-on-suboxone-i-questioned-him-on-why-he-was-on-it-he-said-that-it-was-for-depression-2