October 4, 2026 
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William "Wes" Alden, MD, PhD | Clinical Education Series
Compounded Peptides and the Rules That Govern Them
By William “Wes” Alden, MD, PhD
Peptide drugs range from fully approved medicines with years of outcome data to research chemicals that have never been tested properly in people. In the middle sits compounding, bulk-substance lists, and a set of FDA categories that continue to evolve. Marketing often blurs the differences. Patients and clinicians both need a clear map.
Approved peptide medicines
Insulin and its analogs, the GLP-1 and dual agonists, teriparatide, abaloparatide, many fertility and GnRH agents, eptifibatide, bivalirudin, teduglutide, elamipretide for Barth syndrome, ziconotide, and a long list of others belong here. They have labeled indications, manufacturing standards, and known safety profiles.
Compounding categories and recent changes
Under section 503A, compounding pharmacies may use bulk ingredients that appear on the FDA’s official list or that meet other specific criteria. Substances have been sorted into categories based on the strength of the data and any safety concerns. In April 2026 the agency removed a group of peptides (BPC-157, TB-500, MOTS-c, KPV, Epitalon, Semax, DSIP, LL-37, injectable GHK-Cu, Dihexa, PEG-MGF, and Melanotan II among them) from Category 2 after the nominations were withdrawn. Being removed from Category 2 does not place a substance onto the approved bulk list. Most of these agents remain in a gray zone while further review continues. None is an FDA-approved drug for the regenerative or wellness uses often advertised.
Research-only material
Peptides sold “for research use only” or by chemical suppliers are not made to the standards required for human medicine. Giving them to patients is inappropriate and potentially unsafe. Identity, purity, and sterility cannot be assumed.
Talking with patients who ask
When someone brings up BPC-157, TB-500, MOTS-c, or similar compounds, a straightforward reply usually covers five points: the preclinical science may be interesting; the agent is not FDA-approved for the hoped-for use; current compounding status is uncertain or restricted; research-grade powder must never be injected or taken by people; and proven therapies plus ordinary lifestyle measures still address the same goals of healing, metabolic health, or lower inflammation.
Why the distinction matters
The peptide field contains real pharmaceutical successes and a large amount of loosely regulated marketing. Keeping a bright line between approved drugs, legally compounded preparations when they are permitted, and research chemicals protects patients and keeps the science credible. Interest in new biology can coexist with strict attention to evidence and regulation.
William “Wes” Alden, MD, PhD, is a physician-scientist and internist. His career has included academic medicine, federal clinical research, community practice, and medical philanthropy. He works in the Greater New Orleans area, including Metairie, New Orleans, and the Northshore communities of Mandeville and Covington. His interests include metabolic health, integrative approaches, neurodegenerative conditions, and practical whole-person care. He emphasizes honest evidence and clear communication with patients and families.
This article is for general education and reflects Dr. Alden’s professional perspective. It is not medical advice and does not create a doctor-patient relationship. Results vary from person to person. Many peptides, NAD products, and specialty lipids mentioned here are not FDA-approved for anti-aging, cognitive enhancement, or most of the wellness uses sometimes promoted. Material labeled for research use only should never be given to people. Please consult a qualified clinician about your own situation before starting any evaluation or treatment.
