Veteran Overmedication Prevention Act of 2017 This bill requires the Department of Veterans Affairs (VA) to contract with the National Academies of Sciences, Engineering, and Medicine (or another private, not-for-profit entity with comparable expertise) to review the deaths of all covered veterans who died by suicide during the last five years. A "covered veteran" is any veteran who received VA hospital care or medical services during the five-year period preceding the veteran's death. The review shall include: the total numbers of veterans who died by a violent death or by an accidental death during such period; each veteran's age, gender, race, and ethnicity; a list of medications and substances prescribed to such veterans, as annotated on toxicology reports; a summary of medical diagnoses by VA physicians that led to such prescriptions in cases of anxiety and depressive disorders; the number of instances in which such a veteran was concurrently on multiple medications prescribed by VA physicians; the number of such veterans who were not taking any VA-prescribed medication; the percentage of such veterans treated for anxiety or depressive disorders who received a non-medication first-line treatment compared to the percentage who received medication only; the number of instances in which a non-medication first-line treatment was attempted and deemed ineffective, which led to prescribing medication; descriptions of how the VA determines and updates clinical practice guidelines for prescribing medications and of VA efforts to maintain appropriate staffing levels for mental health professionals; the percentage of such veterans with combat experience or related trauma; identification of VA medical facilities with markedly high prescription rates and suicide rates for treated veterans; an analysis of VA programs that collaborate with state Medicaid agencies and the Centers for Medicare and Medicaid Services; an analysis of VA medical center collaboration with medical examiners' offices or local jurisdictions to determine veteran mortality and cause of death; identification of a best practice model to collect and share veteran death certificate data; an assessment of any apparent patterns based on the review; and recommendations to improve the safety and well-being of veterans. The VA shall ensure that such data is compiled in a manner that allows it to be analyzed across all data fields for purposes of informing and updating VA clinical practice guidelines.