Peptides are short chains of amino acids, the same building blocks that make up proteins. Your body makes thousands of them, and many work as signals: insulin tells cells to take in sugar, and GLP-1 helps control appetite and blood sugar after a meal.
Three very different categories
1. FDA-approved peptide medicines
These have been through clinical trials and are made under strict manufacturing rules. Examples include insulin, semaglutide and tirzepatide (for type 2 diabetes and weight management), teriparatide (for osteoporosis), tesamorelin, and bremelanotide. They are prescribed by a licensed clinician and filled by a pharmacy.
2. Compounded peptides
A licensed compounding pharmacy can sometimes prepare a peptide for an individual patient with a prescription. Which ingredients pharmacies may use is controlled by the FDA, and the list for peptides has been changing through 2026. See our peptide FDA status guide for where things stand.
3. “Research use only” peptides
These are sold online with labels such as “not for human use.” They are not approved medicines, they are not made to pharmacy standards, and what’s in the vial can differ from the label. The FDA has warned sellers who market these products for people to inject. We don’t recommend, link to or sell them.
Why are peptides everywhere right now?
- GLP-1 medicines made peptide injections a mainstream topic.
- Wellness and recovery claims about peptides such as BPC-157 spread quickly on social media, often well ahead of the human evidence.
- Regulation is moving. In 2026 the FDA revisited how several popular peptides are treated for pharmacy compounding.
Questions to ask about any peptide
- Is it an FDA-approved drug, a compounded prescription, or a “research” product?
- What human studies exist, and how large were they?
- Who is prescribing it, and which licensed pharmacy is dispensing it?
- What are the known side effects and unknowns?
If you’re considering peptide therapy, start with how to find a legitimate provider.
FAQ
Are peptides steroids?
No. Anabolic steroids are a different class of molecule. Some peptides affect hormones, but they are chemically unrelated to steroids.
Are peptides legal?
It depends on the peptide and how it’s obtained. An approved or lawfully compounded peptide prescribed by a licensed clinician is legal. Buying unapproved “research” peptides to inject yourself sits outside that system.
Do collagen peptides count?
Collagen peptides are food supplements you eat or drink. They’re a separate topic from prescription or injectable peptides.
Educational only. This page is general information, not medical or legal advice, and it does not include dosing instructions. Talk to a licensed clinician before starting, changing or stopping any treatment. Rules change, so check the date on this page.