Prospective association of psychological pain and hopelessness with suicidal thoughts

•Suicidal thoughts and behaviors are difficult to predict.•Ketamine is associated with rapid, transient changes in suicidal thoughts.•This study sought to identify antecedents of suicidal thoughts post-ketamine.•Psychological pain and hopelessness were not linked with next-day suicidal thoughts.•Suicidal thoughts were linked with next-day psychological pain and hopelessness.