ual dysfunction due to psychological condition?

hi guys i am 25 years old male i am suffering from poor memory and poor concentration and also i am having low desire and weak s ...there is no any organic cause its due to psychological stress as diagnosed by doctor.he has told me to start antidepressant paroxetine but it causes so much sdation that i used to sleep too much so i dont want to be on medicine is there any othere alternative if i dont wish to take antidepressants