OBJECTIVES: To measure the persistence over time of intended and unintended effects on community based depression treatment in the U.S. associated with the FDA warnings on antidepressants and suicidality. In October 2003 the U.S. FDA issued a Public Health Advisory about the risk of suicidality for pediatric patients on SSRI antidepressants; a boxed warning and medication guide were implemented in February 2005, and later extended to young adults aged 19-24. Unintended declines in diagnosis and non-SSRI substitute treatment have been shown immediately following the advisory both for pediatric patients, and for adult patients not targeted by the warnings. Whether those changes persisted is unknown. METHODS: Pediatric, young adult, and adult cohorts with newly diagnosed episodes of depression were created using a national, integrated managed care claims (commercially available from PHARMetrics®, a Unit of IMS, Inc.) from July 1999-June 2006 (n= 55,218 youth; 44,141 young adults; 394,524 adults patients with new episodes). Time series analyses compared post-FDA advisory trends to expected trends based on pre-advisory patterns. RESULTS: Young adult and adult populations mirrored changes in pediatric depression care after the FDA advisory. Reductions in national rates of depression treatment were substantial, returning national diagnosing rates to 1999 levels for pediatric patients and to 2003 levels for adults. Primary care providers continued significant reductions in new diagnoses of depression (50% lower for pediatric, 40% lower for young adult, 30% lower for adult).  Substitute care by psychiatrists or psychologists, psychotherapy, and anxiolytic and atypical antipsychotic medication use did not significantly change from pre-advisory trends. CONCLUSIONS: Declines in depression diagnosis continued after the advisory. Substitute care did not compensate. Spillover to adults continued. Results suggest that the unintended effects were substantial, diffuse, and non-transitory in a large national population. Policy actions are required to counter the unintended consequences of reduced depression treatment.