Résumé
With one million deaths worldwide, suicide is a major health problem. Despite a growing literature on this subject, efficient therapeutic strategies to prevent them are still lacking. New hypotheses to better understand this complex phenomenon are needed. The purpose of this chapter is to focus the study of suicidal behavior regarding pain, especially psychological pain. Unbearable pain is reported as one of the most frequent themes of suicide notes. Psychological pain, or psychache, was originally defined by Shneidman who considered psychache as a constant suicidal behavior. Taking into account social exclusion (source of psychological pain) may help to understand the phenomenology of suicidal act. In addition, there are increased evidence of an overlap between psychological/social pain and physical pain, already identified as risk factors for suicide. There is evidence that an alteration of pain perception may be a factor for suicidal vulnerability. The proposal that pain is core to suicidal behavior may provide new avenues for improving the understanding of the physiopathology (i.e., opioid system) and treatment of suicidal behavior (i.e., pain becoming a therapeutic target).