Are peptides legal in the US?
Some are and some aren’t, depending on whether a peptide is an approved medicine, allowed in compounding, or neither. “Peptide” describes a type of molecule, not a legal category.
The rules below are for the US; other countries differ.
The three kinds of peptides, legally
| Kind | Examples | Legal to use? |
|---|---|---|
| FDA-approved medicines | Semaglutide, tirzepatide, insulin, tesamorelin | Yes, with a prescription |
| Compounded prescriptions | Sermorelin, and others the FDA allows | Yes, with a prescription, from a licensed pharmacy |
| “Research use only” chemicals | BPC-157, TB-500, most online peptides | Not approved for human use |
What does “research use only” mean?
It means the product is sold for lab experiments, not for people. Sellers use the label because selling an unapproved drug for human use is illegal, and the FDA has sent warning letters to sellers who market these products for people anyway.
These products aren’t checked for purity, strength or sterility; see research peptides.
What is FDA Category 2?
Category 2 is the FDA’s list of bulk ingredients that compounding pharmacies may not use because of possible safety risks. In 2023 the FDA added about 19 peptides, including BPC-157, TB-500, ipamorelin and CJC-1295.
What changed for peptides in 2024 and 2026?
In 2024 several peptides, including ipamorelin, CJC-1295, AOD-9604, selank and thymosin alpha-1, moved off the pharmacy (503A) Category 2 list after their nominations were withdrawn. In 2026 most of the rest followed, and in July 2026 an FDA advisory committee recommended allowing six (BPC-157, TB-500, KPV, MOTS-c, epitalon and Semax) in pharmacy compounding.
Leaving Category 2 isn’t an approval, and the FDA still has to make final decisions.
Is compounded semaglutide or tirzepatide legal?
Mostly not anymore. Compounded copies were allowed only while the drugs were in shortage, which ended in December 2024 for tirzepatide and February 2025 for semaglutide.
In April 2026 the FDA also proposed removing both from the list that large compounding facilities can use.
Are peptides legal in sports?
Many are banned. The World Anti-Doping Agency prohibits growth hormone-releasing peptides like CJC-1295, ipamorelin and tesamorelin, plus BPC-157, TB-500, MOTS-c and any substance not approved for human use.
Tested athletes can fail a drug test from a “research” peptide even if it was sold legally.