Generally, if an Ad works properly, it continues to work rather than fading out. Remeron is a viable AD and quite widely used. It is slightly different in the chemical ways it works to the more common SSRI family of ADs like Prozac and its relatives. But not every AD works well in every person. If it has been "only moderately successful", maybe you would be better suited by any of a number of different ADs that as available. Discuss this with your prescribing doc. IF the second AD is also not fully effective for you after a fair trial of a month, make sure you either see a psychiatrist ( if you're being treated by a GOP right now ) or consider a second opinion if you're seeing a psychiatrist at present.