Exploring the Power of Peptides
Exploring Peptides: What They Are, What the Research Says, and What’s FDA-Approved
A plain-language overview from MedClub by Dr. Jenn
MedClub by Dr. Jenn | Palm Beach, FL | Updated October 2026
Read This First
Peptides are a broad category. A few are FDA-approved prescription drugs for specific uses. Many others discussed online are not FDA-approved, and the research behind them varies widely in quality.
This article is general education. It is not medical advice, does not describe expected results, and is not a recommendation to use any product.
What Are Peptides?
Peptides are short chains of amino acids, the same building blocks that make up proteins. Your body makes many peptides naturally, and several of them act as hormones or chemical messengers. Some prescription medicines, including insulin and the GLP-1 medications, are peptide-based.
Because “peptide” describes a chemical structure and not a type of treatment, the term covers everything from fully approved medications to experimental compounds that have only been studied in the laboratory. Knowing which is which matters, and the sections below sort them by regulatory status.
FDA-Approved Peptide Medications
GLP-1 Medications (1)(2)
FDA-approved brand-name drugs
GLP-1 receptor agonists such as semaglutide and the dual GIP/GLP-1 agonist tirzepatide mimic gut hormones involved in blood sugar and appetite signaling. Brand-name versions (for example Ozempic, Wegovy, Mounjaro and Zepbound) are FDA-approved for specific indications, which differ by product. Their approvals rested on large randomized trials, such as STEP 1 for semaglutide and SURMOUNT-1 for tirzepatide.
These medications carry important warnings, including a boxed warning about thyroid C-cell tumors. See our overview of weight loss medication options for more.
Bremelanotide (PT-141) (3)
FDA-approved for one specific use
Bremelanotide is sold as the prescription drug Vyleesi, which is FDA-approved for premenopausal women with acquired, generalized hypoactive sexual desire disorder. It acts on melanocortin receptors in the nervous system. It is not FDA-approved for men or for any other use.
Peptides Not Approved by the FDA
The peptides below are not FDA-approved drugs. We describe what is publicly known about them for educational purposes only. We do not claim that they treat, cure or prevent any condition.
BPC-157 (4)
Investigational • Not FDA-approved
BPC-157 is a synthetic peptide fragment based on a protein found in gastric juice. It has been studied in laboratory and animal models of tissue injury. A 2025 systematic review of BPC-157 in orthopaedic sports medicine found the published evidence to be largely preclinical, and well-controlled human trials remain limited.
TB-500 and Thymosin Beta-4 (5)
Investigational • Not FDA-approved
Thymosin beta-4 is a naturally occurring protein involved in cell movement and tissue repair processes, and it has been examined in laboratory research. “TB-500” is the name commonly used for a synthetic fragment related to it. Research findings on the natural protein should not be assumed to apply to TB-500.
Ibutamoren (MK-677) (6)
Investigational • Not FDA-approved
Ibutamoren is an oral compound that mimics ghrelin and has been studied for its effect on growth hormone and IGF-1 levels. A randomized trial in healthy older adults examined hormone levels and body composition. Questions about long-term safety, including effects on blood sugar, mean it remains a research compound.
Other Peptides You May See Mentioned
Not FDA-approved
Online sources often discuss Melanotan II, CJC-1295, Ipamorelin, Semax, Selank, Epitalon and GHK-Cu. None is an FDA-approved drug. Their evidence varies, and for several of them published human research is limited or comes from outside the United States. If you read claims about any of them, ask a licensed clinician what is actually known.
At a Glance
Swipe sideways on small screens to see the full table.
| Peptide | FDA Status | Research Summary |
|---|---|---|
| Semaglutide, tirzepatide | Approved as brand-name drugs for specific indications | Large randomized trials; boxed warning |
| Bremelanotide (PT-141) | Approved as Vyleesi for one specific indication | Clinical trials in premenopausal women |
| BPC-157 | Not approved | Mostly preclinical; limited human data |
| TB-500 / thymosin beta-4 | Not approved | Laboratory research on the natural protein |
| Ibutamoren (MK-677) | Not approved | Small randomized trial; long-term safety unclear |
A Note on Compounded Peptides
- Compounded medications are made by a pharmacy for an individual patient. They are not FDA-approved and are not reviewed by the FDA for safety, effectiveness or quality.
- The FDA regulates which bulk substances pharmacies may use in compounding, and its lists for several peptides have been changing. Check the FDA’s compounding page for the current status.
- A change in compounding eligibility is not the same as FDA approval of a drug.
- Any prescription must come from a licensed clinician after an appropriate evaluation and be filled by a licensed pharmacy.
Safety & Important Information
Important Safety Information
- Peptides that are not FDA-approved have not been shown by the FDA to be safe or effective for any use.
- Do not buy peptides labeled “research use only” or sold online without a prescription. Their purity, dose and sterility are unverified, and they are not intended for human use.
- Possible side effects depend on the specific product. Injectable products can cause injection-site reactions, and allergic reactions are possible with any medication.
- Tell your clinician if you are pregnant, breastfeeding, planning a pregnancy, have a history of cancer, or take other medications or supplements.
- GLP-1 medications carry a boxed warning for the risk of thyroid C-cell tumors and are not appropriate for everyone.
- Seek medical care right away for severe allergic symptoms, trouble breathing, chest pain, or other serious symptoms.
Considerations Before Talking With a Provider
- Ask whether a product is FDA-approved, and for which specific use.
- Ask where it is made and which licensed pharmacy would prepare it.
- Ask what is known (and not known) from human studies.
- Bring a list of your medications and conditions.
- Discuss whether an FDA-approved option exists for what you are asking about.
Important Disclaimer
This article is for general educational purposes only and is not medical advice. It does not create a patient relationship and is not meant to diagnose, treat, cure or prevent any condition. Individual responses to any medication vary. Regulatory status and research change over time, so always confirm current information with a licensed healthcare provider and the FDA.
Sources
Questions About Peptides or Weight Management?
Schedule a consultation with Dr. Jenn to discuss which options, if any, are right for you.
Call (561) 214-3323
333 Southern Blvd STE 404, West Palm Beach, FL 33405
These statements have not been evaluated by the Food and Drug Administration. Compounded medications are not FDA-approved. Products discussed here that are not FDA-approved are not intended to diagnose, treat, cure, or prevent any disease. A consultation with a licensed provider is required before any treatment.