i recently started taking tamoxifen and have to for the next five years (im post breast cancer) I also have genital herpes. While on chemotherapy i noticed my outbreaks were more frequent. Now that i've started taking the tamoxifen i have gotten one of the worse outbreaks i have ever had. I'm also on effexor for the hot flashes. Is this some kind of side effect? why am i getting these outbreaks and so bad and painful?