"The purpose of an antidepressant is to improve mood." I'd say that their effect is that they reduce the amplitude of emotions, so to speak. You get sad, but n

"The purpose of an antidepressant is to improve mood." I'd say that their effect is that they reduce the amplitude of emotions, so to speak. You get sad, but not -as- sad; however you also don't get as happy as you might have been otherwise. This is a reason that some people don't like taking such drugs: they feel it takes away their emotions and transform their personalities.