OBJECTIVE: To identify circumstances and characteristics of suicidal behavior among early (aged 10-14 years) and late (aged 15-18 years) adolescents from a cohort of youth who were prescribed antidepressant medication. METHODS: In-depth reviews of all available medical records were performed for 250 randomly chosen confirmed episodes of suicidal behavior identified as part of a large retrospective cohort study of antidepressant users and suicidal behavior. Study data were obtained from Tennessee Medicaid records and death certificates from January 1, 1995, to December 31, 2006. Medical records and autopsy reports for cases identified from electronic data were adjudicated by 2 investigators blinded to exposure status and classified by using a validated scale. RESULTS: Of the 250 cases reviewed, 65.6% were female and 26.4% were aged 10 to 14 years. Medication ingestion was the most frequent method of suicidal behavior for both early and late adolescents; however, early adolescents were significantly more likely to use hanging as a method of suicide. Nearly one-half of the adolescents had previously attempted suicide. Early adolescents were significantly more likely to have a history of sexual abuse and significantly less likely to have a history of substance abuse. Early adolescents were also significantly more likely than older adolescents to have a history of a psychotic disorder and to report hallucinations before the suicide attempt. CONCLUSION: Suicidal behavior among early and late adolescents prescribed antidepressant medication differed in terms of methods used, previous psychiatric history, and proximal symptoms. Copyright © 2011 by the American Academy of Pediatrics.