A fair number of posters - since this chem's proliferation has really ramped up over the past few months - have come here posting about coming off of binges as short as a week and suffering a wide variety of physical and, more prominently, emotional and psychological issues as a result.
Temporary (in most cases) psychosis and vision problems coupled with depression and a feeling of being "disconnected" or somehow "damaged" in a way that feels irreparable but probably for the most part isn't seem to be the most commonly discussed implications of overuse.