When were peptides first used as medicine?

1922. Insulin — a peptide hormone — was first used to treat a patient (14-year-old Leonard Thompson) on January 11, 1922, and it has saved lives ever since.

Are peptide medicines FDA-approved?

Many are. The FDA has approved dozens of peptide and protein medicines, from insulin to modern GLP-1 medications. That said, not every peptide sold online is one of them — approval status is one of the things to check.

If peptides are so established, why the controversy?

The established part is the science of peptides as medicine. The controversy is about specific, newer peptides sold without approval or testing — a sourcing-and-evidence problem, not a reason to dismiss the whole category.

How Long Have Peptides Been Used in Medicine?

Are peptides a new fad? Not even close.

A lot of the online noise treats peptides as some brand-new biohack. The calendar disagrees. Peptide medicine is more than a century old.

It started in 1922

On January 11, 1922, a critically ill 14-year-old named Leonard Thompson became the first person treated with insulin — a peptide hormone (UMass Chan Medical School, NobelPrize.org). It turned a death sentence into a manageable condition, and it’s still saving lives today.

Dozens of peptide medicines since

Insulin was the first, not the last. The FDA has since approved dozens of peptide and protein medicines across many conditions — a body of approved therapeutics catalogued in the medical literature (THPdb, NIH/PMC). Peptides have become a steady, growing part of the approved toolkit, not a sidebar.

The GLP-1 era you’ve heard about

The medications dominating headlines are a recent chapter of the same story:

Exenatide (Byetta) — the first GLP-1 receptor agonist, FDA-approved in 2005
Semaglutide — Ozempic (2017), then Wegovy for weight management (2021)
Tirzepatide — Mounjaro (2022)

(NIH/PMC review). The active ingredients in all of them are peptides.

So where does the controversy come from?

Here’s the honest nuance. The science of peptides as medicine is well-established. The controversy is about specific, newer peptides being sold online without FDA approval and without testing. That’s a sourcing and evidence question — not a reason to treat the whole category as fringe.

Which is exactly what the next read is about: Legitimate vs. grey-market peptides →

This article is general education, not medical advice, and is not intended to diagnose, treat, cure, or prevent any disease. Whether any therapy is appropriate for you is a decision for a licensed provider during a Provider Evaluation.

Sources: UMass Chan — first insulin injection, 1922 · NobelPrize.org — the insulin discovery · THPdb: FDA-approved peptide & protein therapeutics (NIH/PMC) · GLP-1 receptor agonist review (NIH/PMC)