Darrin Mangiacarne, DOADDICTION MEDICINE
Addiction Medicine Expert Witness · Fishers, Indiana

Darrin Mangiacarne

DO  ·  MPH  ·  CPE  ·  DFASAM  ·  DFAOAAM

Independent, evidence-based expert opinion on the standard of care in addiction medicine and treatment.

Board-certified addiction medicine physician, Chief Medical Officer of Banyan Treatment Centers, and President of the American Osteopathic Academy of Addiction Medicine. Available to plaintiff and defense counsel for case review, expert reports, depositions, and trial testimony.

Discuss a Matter View Services
Darrin Mangiacarne, DO
15+Years leading addiction medicine & behavioral health operations
30+Medical-legal matters, plaintiff and defense
20Treatment facilities across 10 states overseen as CMO
18States of active medical licensure
About

A practicing physician who also runs the system.

Since 2021, Dr. Mangiacarne has served as Chief Medical Officer of Banyan Treatment Centers, overseeing medical, addiction, and psychiatric services across 20 treatment facilities in 10 states. He continues to provide direct patient care.

He brings more than 15 years of physician-executive experience leading multi-site addiction medicine and behavioral health operations. As Regional Medical Director at Spero Health (2019–2021), he directed medical operations for outpatient office-based opioid treatment programs across a multi-state network. Earlier, he was Chief Medical Officer of Fairbanks Hospital, a 90-bed behavioral health hospital in Indianapolis.

He is President of the American Osteopathic Academy of Addiction Medicine (AOAAM) and a Distinguished Fellow of both ASAM and AOAAM. He holds board certification in Addiction Medicine (ABPM) and Family Medicine (AOBFP), a Master of Public Health in Healthcare Policy and Administration, and the Certified Physician Executive (CPE) credential.

That combination of bedside practice, medical-director oversight, and national policy leadership informs his independent medical-legal practice, with more than 30 matters for plaintiff and defense counsel since 2016.

Expert Witness Services

Medical-Legal Expert Witness Services

Objective analysis of the standard of care in addiction medicine and substance use disorder treatment, grounded in current clinical practice and multi-site operational experience. Retained on more than 30 matters since 2016 by both plaintiff and defense counsel, including medical malpractice, wrongful death, disability, and national prescription opioid litigation.

30+Matters retained since 2016
Both sidesPlaintiff and defense retentions
DeposedIn state and federal courts and administrative proceedings
ZeroDaubert challenges to date

Case Types

  • Medical malpractice and professional negligence
  • Wrongful death
  • Disability and workers’ compensation
  • National prescription opioid litigation
  • Class actions involving recovery programs

Areas of Expertise

  • Standard of care in addiction medicine and SUD treatment
  • Detoxification, withdrawal management, and residential treatment
  • Medication for opioid use disorder (MAT/MOUD) and opioid prescribing
  • Suicide risk assessment and patient safety in behavioral health
  • Standard of care for medical oversight and staffing in treatment settings

Defendant Settings Reviewed

  • Residential and inpatient addiction treatment centers
  • Hospitals and behavioral health hospitals
  • Outpatient, urgent care, and family practice prescribers
  • Correctional health care
  • Surgery centers
01

Case Review

Early, candid assessment of the clinical merits of a matter to help counsel evaluate strengths, weaknesses, and next steps.

02

Standard-of-Care Analysis

Evaluation of care in detoxification, residential, inpatient, and outpatient settings, including medication for opioid use disorder, prescribing, monitoring, and risk assessment.

03

Medical Record Review

Methodical review and chronology of medical, nursing, pharmacy, and program records to establish what occurred and when.

04

Expert Reports

Clear, well-supported written opinions prepared to withstand scrutiny and written so non-clinicians can follow them.

05

Depositions

Prepared, composed, and precise testimony under examination, consistent with the written record.

06

Trial Testimony

Credible courtroom testimony that explains complex addiction medicine concepts to judges and juries.

Serving Plaintiff AttorneysDefense AttorneysInsurersLicensing Boards

A case list and deposition history are available to retaining counsel on request. Engagements are accepted subject to a conflict check.

Credentials at a Glance

Training, certification, and leadership

A summary of qualifications. A full curriculum vitae is available on request.

Board Certification

  • Addiction MedicineAmerican Board of Preventive Medicine (ABPM)
  • Family MedicineAmerican Osteopathic Board of Family Physicians (AOBFP)
  • Certificate of Added Qualifications in Addiction MedicineAOBFP

Distinguished Fellowships

  • DFASAMDistinguished Fellow, American Society of Addiction Medicine
  • DFAOAAMDistinguished Fellow, American Osteopathic Academy of Addiction Medicine

Executive & Public Health

  • Certified Physician Executive (CPE)
  • Master of Public HealthHealthcare Policy & Administration, University of Southern Mississippi

Medical Education

  • Doctor of Osteopathic MedicinePhiladelphia College of Osteopathic Medicine
  • Family Medicine ResidencySt. Luke’s Hospital, Allentown, PA
  • Addiction Medicine FellowshipGeisinger Health System (Marworth)

National & State Leadership

  • President, AOAAM2024 – Present; Board of Trustees since 2019
  • President, Indiana Society of Addiction Medicine2018 – 2020
  • Chair, Indiana Attorney General’s Task Force on Drug Abuse2017 – 2019

Current Role

  • Chief Medical OfficerBanyan Treatment Centers, since 2021
  • 20 facilities · 10 statesMedical, addiction, and psychiatric services

Active medical licensure in 18 states: Alaska, California, Colorado, Delaware, Florida, Georgia, Illinois, Indiana, Kentucky, Michigan, Mississippi, New Jersey, North Carolina, Ohio, Pennsylvania, South Carolina, Tennessee, Virginia.

Why Work With Me

Credibility built in practice, not just on paper.

1

Current, active practice

My opinions reflect how addiction medicine is practiced today. I still see patients and oversee medical care across a multi-state treatment organization.

2

System-level perspective

Experience as CMO, regional medical director, and health plan medical director informs how policies, staffing, and oversight bear on the standard of care in a given case.

3

National standing in the field

President of AOAAM and a Distinguished Fellow of ASAM and AOAAM, with dual board certification.

4

Multi-state reach

Licensed in 18 states, with direct experience in the operational and regulatory differences between them.

5

Balanced and independent

Retained by both plaintiff and defense counsel and never the subject of a Daubert challenge. My conclusions follow the evidence and the standard of care.

6

Clear communication

Complex clinical issues explained plainly and precisely, in written reports and in testimony, for attorneys, judges, and juries.

Publications

Publications

President’s Message columns written as President of the American Osteopathic Academy of Addiction Medicine and published in the Journal of Addictive Diseases (Taylor & Francis). Newest first.

  1. 2026

    President’s Message

    Mangiacarne D. Journal of Addictive Diseases. 2026;44(4), 444–445. doi:10.1080/10550887.2026.2728791

    Argues that medical directors should not report to master’s-level therapists or non-physician clinical directors, calling this inverted hierarchy a patient-safety and liability issue that conflicts with AMA and ASAM guidance on physician leadership of the care team.

  2. 2026

    President’s Message: The Perilous Illusion of Supervised Injection Sites

    Mangiacarne D. Journal of Addictive Diseases. 2026;44(3), 233–234. doi:10.1080/10550887.2026.2680828

    Contends that supervised injection sites do not treat addiction, citing mixed population-level evidence from Canada and community harms documented in Alberta, and urges investment in MOUD, residential treatment, contingency management, and long-term recovery support instead.

  3. 2026

    President’s Message: Beyond Managed Chaos: Advocating for Guideline Reform in Polypharmacy Oversight

    Mangiacarne D. Journal of Addictive Diseases. 2026;44(1), 1–2. doi:10.1080/10550887.2025.2577532

    Uses a case example to show how siloed prescribing around buprenorphine can sustain unmanaged polypharmacy, and calls for SUD screening before stimulants or sedative-hypnotics are prescribed in comorbid cases and for real-time care coordination.

  4. 2025

    President’s Message: The Dangers of Ketamine Clinic Proliferation

    Mangiacarne D. Journal of Addictive Diseases. 2025;43(4), 297–298. doi:10.1080/10550887.2025.2536889

    Warns that the rapid growth of for-profit, minimally overseen off-label ketamine clinics endangers patients with substance use disorders, and calls for mandatory SUD screening and stricter oversight.

  5. 2025

    President’s Message: The Dangerous Mirage of Medical Marijuana

    Mangiacarne D. Journal of Addictive Diseases. 2025;43(3), 199–200. doi:10.1080/10550887.2025.2504237

    Argues that the evidence for medical marijuana is weak and its normalization undermines recovery, and calls for potency caps, mandatory addiction screening, and sanctions on financially driven prescribing.

  6. 2025

    President’s Message

    Mangiacarne D. Journal of Addictive Diseases. 2025;43(2), 105–106. doi:10.1080/10550887.2025.2465947

    His first message as AOAAM President, making the case for integrating spirituality alongside medication-assisted treatment to improve recovery outcomes.

Contact

Discuss a matter

Please send a short description of the matter, the parties involved (for a conflict check), and any relevant deadlines. Do not send confidential records or protected health information until an engagement is confirmed.

Location
Fishers, Indiana · Engagements nationwide
Professional Profile
LinkedIn →
Curriculum Vitae
Available on request

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