Blog/Expert Witness Guide

Peptide Therapy Expert Witness: What Attorneys Need to Know in 2026

What the work actually involves, what credentials survive cross-examination, and how to decide whether your case needs a subspecialist.

August 19, 2026·8 min read·Dr. Fady Hannah-Shmouni, MD FRCPC ABIM

Peptide therapy cases have become one of the fastest-growing categories in medical malpractice and personal injury litigation. Compounded BPC-157, TB-500, growth hormone secretagogues, and similar compounds are now prescribed through telehealth platforms, direct-to-consumer clinics, and anti-aging practices at a scale that was barely imaginable five years ago.

When something goes wrong, attorneys face a problem that most expert witness directories are not built to solve: finding someone who actually knows this field.

This guide explains what a peptide therapy expert witness does, what credentials matter under cross-examination, how to evaluate whether your case requires a subspecialist, and what questions to ask before you retain anyone.

Why Peptide Cases Are Different From Standard Malpractice

Most medical malpractice cases turn on a well-established standard of care. The expert reviews the record, identifies the deviation, and explains it to the jury. Peptide therapy cases rarely work that way.

Many peptides prescribed in clinical settings sit in a regulatory grey zone. BPC-157 and TB-500, for example, are not FDA-approved for human use but are widely compounded and prescribed off-label. Growth hormone secretagogues like ipamorelin and CJC-1295 occupy a similarly ambiguous position. When standard of care is genuinely contested, or when off-label prescribing is central to liability, the expert's job is more complex than pointing to a guideline violation.

The expert must be able to:

  • Explain what the clinical evidence actually supported at the time of treatment, not what guidelines say today
  • Distinguish between legitimate off-label use and a departure from reasonable medical practice
  • Speak to the specific compounding pharmacy record, the dosing protocol, and whether baseline labs were ordered and reviewed
  • Hold up under cross-examination from opposing counsel who will probe the evidentiary basis for every claim

A generalist who has treated diabetes or thyroid disease but has no direct experience with peptide protocols will struggle on all four points. Opposing counsel will find that gap quickly.

What a Peptide Therapy Expert Witness Actually Does

The work begins before any deposition or trial. A qualified peptide therapy expert witness should be able to provide:

Record Review and Chronology

Peptide cases typically involve fragmented records: telehealth transcripts, compounding pharmacy logs, lab panels ordered at different facilities, and clinic notes that may be incomplete or missing entirely. A thorough record review maps all of this onto a single timeline tied to source pages, so the opinion is traceable and defensible.

Missing baselines are a recurring issue. If a provider prescribed a growth hormone secretagogue without ordering IGF-1 levels, that gap is clinically significant. The expert needs to recognize it, document it, and explain its relevance to the standard of care analysis.

Standard of Care Opinion

The written opinion is the core deliverable. It should measure the care provided against the guidelines and evidence that were in force at the time of treatment, not retroactively applied standards. This distinction matters at trial. An opinion that conflates what was known in 2022 with what was published in 2025 is vulnerable on cross-examination.

The opinion should also address the specific compound involved. BPC-157 cases raise different questions than ipamorelin cases. A credible expert knows the literature on each, including its limitations.

Deposition and Trial Testimony

The expert needs to explain complex pharmacology and clinical reasoning to a lay jury without losing accuracy. They also need to anticipate and respond to challenges from opposing counsel, including challenges to the scientific basis of their opinion under Daubert or its provincial equivalents in Canadian proceedings.

The Subspecialty Problem With Generalist Experts

The most common mistake attorneys make in peptide cases is retaining a board-certified endocrinologist whose practice is focused on diabetes and thyroid disorders. The credentials look right. The CV survives voir dire. But the depth of knowledge does not hold up.

Peptide therapy, testosterone replacement, growth hormone secretagogues, and SARMs are a distinct clinical subspecialty within endocrinology. An expert who has not actively worked in this area will not know:

  • Which compounded peptide formulations were available from which pharmacies in a given period
  • What dosing protocols were considered within the range of accepted practice versus experimental
  • How the evidence base for a specific peptide was understood at the time of treatment
  • Where the field was genuinely unsettled and where it was not

That last point is particularly important. Opposing counsel will argue that the field is too unsettled to establish a standard of care at all. A subspecialist can rebut that argument precisely because they know where the settled science ends and the grey zone begins.

Evaluating Whether Your Case Needs a Peptide Subspecialist

Not every case involving a peptide compound requires a subspecialist. But several fact patterns consistently do:

Off-label prescribing is central to liability.

If the core question is whether the provider should have prescribed this compound at all, or whether the dosing was within accepted practice, you need someone who can speak to what "accepted practice" actually meant in this context.

The opposing expert is a generalist.

If the other side has retained a general endocrinologist with no peptide experience, a subspecialist on your side creates a credibility asymmetry that matters to the jury.

The case involves a telehealth or direct-to-consumer clinic.

These settings often have thinner records, abbreviated intake processes, and limited follow-up. The expert needs to know what a well-run peptide practice looks like in order to identify where this one fell short.

Compounding pharmacy records are in dispute.

The chain of custody from prescription to compounded product to patient is a distinct area of clinical and regulatory knowledge. An expert who has never reviewed compounding pharmacy logs will miss things.

The case involves SARMs or anabolic steroids alongside peptides.

Selective androgen receptor modulators like ostarine or ligandrol are often co-prescribed with peptides in performance or anti-aging contexts. The expert needs to understand the combined protocol, not just one compound in isolation.

Credentials That Hold Up Under Cross-Examination

When you are evaluating a peptide therapy expert witness, credential depth matters more than credential breadth. Here is what to look for:

Board certification in endocrinology. This is the baseline. It establishes that the expert has formal training in the hormonal systems involved. ABIM certification in endocrinology, diabetes, and metabolism is the relevant US credential; FRCPC is the Canadian equivalent.

Active clinical and research work in the relevant subspecialty. A physician who last treated a hormone therapy patient five years ago is a weaker witness than one with a current clinical practice. Active research credentials, including faculty appointments and peer-reviewed publications, strengthen the opinion's scientific foundation.

Experience with the specific compounds at issue. Ask directly: has the expert reviewed cases involving BPC-157, or ipamorelin, or the specific SARM in your case? Have they published or lectured on these compounds? Can they speak to the compounding pharmacy record from clinical experience?

Familiarity with the telehealth and direct-to-consumer context. Many peptide cases originate in these settings. An expert who has only practiced in academic medical centers may not understand the operational realities of a telehealth peptide clinic, which affects how they assess the standard of care.

Willingness to testify for both plaintiff and defence. An expert who only works for one side is a weaker witness. Opinions that follow the record, not the retaining party, are more credible to juries and more defensible under cross-examination.

What to Ask Before You Retain

Before engaging any expert for a peptide therapy matter, ask these questions:

  1. 01What is your direct clinical experience with the specific compound or protocol at issue?
  2. 02Can you explain the standard of care for this compound as it existed at the time of treatment, not today?
  3. 03Have you reviewed compounding pharmacy records in prior cases? What do you look for?
  4. 04How do you handle cross-examination on the evidentiary basis for your opinion when the compound is off-label?
  5. 05Have you testified for both plaintiff and defence counsel?
  6. 06What is your process for identifying missing records or incomplete baselines?

The answers will tell you quickly whether the expert has genuine subspecialty depth or is a generalist who has added peptide cases to their practice without the underlying clinical foundation.

hormon.ai: A Practice Built for These Cases

hormon.ai is the medicolegal practice of Dr. Fady Hannah-Shmouni, a board-certified endocrinologist (ABIM + FRCPC) with Yale training and a faculty appointment at UBC. The practice is built entirely around hormone, peptide, and AI medicine cases and serves both plaintiff and defence counsel, as well as insurers and regulatory bodies.

Services include record review and chronology, standard of care opinions, deposition and trial testimony, independent medical examinations, and identification of missing records. The practice covers BPC-157, TB-500, growth hormone secretagogues, compounded research peptides, TRT, GLP-1 agonists, SARMs, and anabolic steroids, as well as cases involving agentic AI in clinical prescribing workflows.

Every opinion is tied to source pages and the evidence in force at the time of treatment. If your case involves any of these areas, you can enquire about a matter directly at hormon.ai.

Frequently Asked Questions

Common questions from counsel.

What is a peptide therapy expert witness?
A peptide therapy expert witness is a physician, typically a board-certified endocrinologist, who reviews medical records and provides written opinions and testimony in litigation involving compounded peptides such as BPC-157, TB-500, or growth hormone secretagogues. Their role is to establish or contest the standard of care for the specific compound and protocol at issue.
Why can't a general endocrinologist serve as an expert in a peptide case?
General endocrinologists typically focus on diabetes, thyroid, and adrenal disorders. Peptide therapy, testosterone replacement, and growth hormone secretagogues are a distinct subspecialty. A generalist may lack direct clinical experience with the specific compounds, dosing protocols, and compounding pharmacy records involved, which creates vulnerability under cross-examination.
What does "standard of care" mean when a peptide is off-label?
Off-label prescribing is legal and common, but it does not eliminate the standard of care. The expert must assess whether the provider's decision to prescribe the compound, and the way they prescribed it, was consistent with what a reasonable practitioner with relevant subspecialty knowledge would have done at the time of treatment, given the evidence then available.
Can a peptide therapy expert witness testify for both plaintiff and defence?
Yes, and they should be willing to. An expert who only works for one side is a weaker witness because their impartiality is easier to challenge. A credible expert follows the record and the evidence, not the retaining party's preferred outcome.
What records are most important in a peptide malpractice case?
Clinic notes, compounding pharmacy logs, lab panels (particularly baseline hormone levels), telehealth transcripts, and any records showing informed consent or patient education. Missing baseline labs are a common and significant issue in these cases.
How do I know if my case requires a peptide subspecialist rather than a general endocrinologist?
If off-label prescribing is central to liability, if the opposing expert is a generalist, if the case involves a telehealth or direct-to-consumer clinic, or if compounding pharmacy records are in dispute, you likely need a subspecialist. Cases involving co-prescribed SARMs or anabolic steroids alongside peptides almost always require one.
What credentials should I look for in a peptide therapy expert witness?
Board certification in endocrinology (ABIM or FRCPC), active clinical and research work in hormone and peptide medicine, direct experience with the specific compounds at issue, familiarity with telehealth and compounding pharmacy records, and a track record of testifying for both plaintiff and defence counsel.

Retain the practice.

For peptide, hormone and AI medicine litigation — retained by plaintiff and defence counsel.

Enquire about a matter