Peptide Therapy: Uses, Types, and What's Actually FDA-Approved

What they are

What Peptides Are

Peptides are short chains of amino acids — usually fewer than 50 — that act as signaling molecules. The body produces thousands naturally (insulin, oxytocin, glucagon, GHRH). Therapeutic peptides mimic or modulate these endogenous signals.

Calling something a “peptide” says nothing about whether it works, whether it is safe, or whether it is legal. The category spans blockbuster FDA-approved drugs and unregulated research chemicals sold by mail.

FDA-approved

The Peptides That Are Actually FDA-Approved

A short list of peptides has full FDA approval with the manufacturing and safety data approval requires:

• ·Semaglutide (Ozempic, Wegovy, Rybelsus) — diabetes and obesity.
• ·Tirzepatide (Mounjaro, Zepbound) — diabetes and obesity.
• ·Tesamorelin (Egrifta) — HIV-associated lipodystrophy; a GHRH analog.
• ·Liraglutide (Saxenda, Victoza) — obesity and diabetes.
• ·PT-141/bremelanotide (Vyleesi) — premenopausal HSDD.
• ·Various insulin analogs.

Compounded / gray-market

Compounded and Research-Chemical Peptides

The peptides most heavily marketed for performance and longevity are not FDA-approved:

• ·BPC-157 — claimed for tendon, joint, and GI healing. Human evidence is essentially absent; nearly all data is rodent.
• ·TB-500 (thymosin beta-4 fragment) — claimed for muscle and tissue repair. Limited human data.
• ·GHK-Cu — copper peptide, mostly topical evidence in dermatology.
• ·CJC-1295, ipamorelin, sermorelin — GH secretagogues. Sermorelin's branded product was discontinued; current use is compounded.
• ·Selank, semax — Russian-origin nootropics with no U.S. approval.
• ·Melanotan II — tanning peptide; serious adverse events documented.

In late 2023 the FDA placed many of these on its 503A category 2 list, narrowing the legal ground for routine compounding.

Evidence

Honest Evidence Levels

• ·Strong human evidence: GLP-1 and dual-incretin peptides; tesamorelin for the labeled indication.
• ·Moderate human evidence: GH secretagogues for confirmed adult GH deficiency.
• ·Limited human evidence: BPC-157, TB-500 — promising mechanism, mostly rodent data.
• ·Topical or local evidence only: GHK-Cu in dermatology.
• ·Anti-aging / longevity outcome data: essentially none for the marketed compounded peptides.

Risks

Real Risks — Source, Sterility, Dosing

The risk of compounded peptide therapy is rarely the molecule itself. It is the supply chain.

• ·Source. Many clinics obtain product from suppliers not intended for human use; identity and purity vary.
• ·Sterility. Self-injection of contaminated peptide has produced documented infections and sepsis.
• ·Dosing. Without FDA-approved labeling, dosing is extrapolated from animal studies; safe-dose data is thin.
• ·Long-term effects on cancer biology, insulin signaling, and cardiovascular risk are not fully characterized.

The physician version

What Legitimate Peptide Prescribing Looks Like

A physician program that uses peptides responsibly looks different from a clinic that sells them:

• ·A specific documented clinical indication the chosen peptide actually addresses.
• ·FDA-approved product where one exists for the indication.
• ·Compounding only from 503A/503B pharmacies operating within current FDA guidance.
• ·Baseline labs, hormone panel where relevant, structured follow-up.
• ·Honest conversation about what the evidence does and does not support.