The main symptom of sad nipple syndrome is the appearance of a series of negative emotional manifestations such as depressed mood, depression, aggression, tears, etc., especially sadness, when touching one’s nipples or stimulation of one’s nipples by other people. This symptom may be caused by a conditioned stimulus that establishes a conditioned reflex, especially the emotional response of sadness once the nipple is stimulated. It is possible that such symptoms and performance may be caused by adverse childhood experiences, especially growing up in a very strict family environment, which may produce the opposite emotional response to nipple stimulation, such as nervousness, anxiety, depressed mood, sadness, etc. Once the sad nipple syndrome appears, it needs to be actively treated, especially psychotherapy, most often using cognitive behavioral therapy, humanistic therapy, psychoanalytic methods, etc.