The FDA requires all antidepressants, including duloxetine, to carry a black box warning stating that antidepressants may increase the risk of suicide in persons younger than 25. This warning is based on statistical analyses conducted by two independent groups of the FDA experts that found a 2-fold increase of the suicidal ideation and behavior in children and adolescents, and 1.5-fold increase of suicidality in the 18–24 age group.
To obtain statistically significant results the FDA had to combine the results of 295 trials of 11 antidepressants for psychiatric indications. As suicidal ideation and behavior in clinical trials are rare, the results for any drug taken separately usually do not reach statistical significance.
Several commentators noted that the data FDA used in their analysis of duloxetine-associated suicidality may have been incomplete. According to Arif Khan, the Summary Basis of Approval used by the FDA to approve duloxetine for depression contained only the mention of two completed suicides out of 3490 patients, and the rest of the data was not sufficient to "conduct any meaningful analysis." Jeanne Lenzer wrote in The Independent and Slate Magazine, and this fact was also confirmed by a Lilly spokesman, that another two completed suicides, which occurred in the depression studies ran by the Lilly's Japanese partner Shionogi, have not been reported to the FDA. According to Lenzer, four completed suicides also occurred in the trials of duloxetine for stress urinary incontinence (SUI). As these trials failed, the FDA initially insisted that any information about them is a commercial secret and cannot be released. Later, in a short statement the FDA acknowledged that in SUI trials eleven suicide attempts occurred in persons taking duloxetine vs none in the placebo group.
A series of four cases of duloxetine-associated suicidality has been reported. In all four cases depressed patients began having suicidal thoughts after starting on duloxetine or increasing its dose. These thoughts stopped, and the patients returned to normal after duloxetine was discontinued, and they were switched to another antidepressant.
A suicide of 19-year-old Traci Johnson, a healthy volunteer in a duloxetine clinical pharmacology study, was highly publicized. For about a month she had been given high doses of duloxetine, and then she was switched to placebo. Four days after the switch, she hanged herself in the bathroom of Lilly Laboratory for Clinical Research. The New York Times article mentioned a withdrawal syndrome as a possible reason for this suicide.