As of October 2026, FDA has posted 29 warning letters that name a peptide sold online or compounded without approval, 12 of them dated 2026. Retatrutide, which has no FDA approval, is named in 21. Every row is a regulatory fact from the letter on fda.gov.
Regulatory fact. Counted by letter date from the table below. FDA sent 5 on March 31, 2026 and 5 on August 24, 2026.
New trials, FDA changes and side-effect reports, written in plain English. Every result says whether it was tested in people or in animals.
Newest first. Each row gives the letter date, who FDA sent it to, the peptides it names and what it cited, with a link to the letter on fda.gov. Filter by recipient, or link to a row by its anchor, such as #wl-734884.
| Letter date | Sent to | Peptides named | What FDA cited |
|---|---|---|---|
| Aug 24, 2026Posted Sep 1, 2026 | NuScience Peptides LLCOnline peptide sellerRead the letter on fda.gov | FDA said the company sold bacteriostatic water beside a "peptide calculator," which it called a resource for preparing an injectable drug for a person. | |
| Aug 24, 2026Posted Sep 1, 2026 | Peak Performance PeptidesOnline peptide sellerRead the letter on fda.gov | Asked for a written response within 15 business days and warned of seizure and injunction if the violations are not fixed. | |
| Aug 24, 2026Posted Sep 1, 2026 | Peptide Partners LLCOnline peptide sellerRead the letter on fda.gov | FDA quoted product pages that described tesamorelin trial results in people with HIV-associated fatty liver disease, and named the "Reconstitution Solution (BAC)" as a drug. | |
| Aug 24, 2026Posted Sep 1, 2026 | Royal Peptides LLCOnline peptide sellerRead the letter on fda.gov | FDA said the bacteriostatic water, "peptide guide" and "peptide calculator" together gave buyers the means to prepare an injectable drug for a person. | |
| Aug 24, 2026Posted Sep 1, 2026 | TXP Innovations LLC dba Tex PeptidesOnline peptide sellerRead the letter on fda.gov | Six peptides plus "Bacteriostatic Water 0.9% Benzyl Alcohol," each named as an unapproved new drug. | |
| Jun 17, 2026Posted Jun 23, 2026 | Wholesale PeptideOnline peptide sellerRead the letter on fda.gov |
| FDA quoted claims that Prostamax treats an enlarged prostate and chronic prostatitis, and said Prostamax and gonadorelin were unapproved new drugs. |
| Mar 31, 2026Posted Apr 7, 2026 | Gram PeptidesOnline peptide sellerRead the letter on fda.gov | FDA said the "Research Use Only" and "not intended for human consumption" labels did not change what the website showed, and that the bacteriostatic water sold beside the peptides is itself a drug. | |
| Mar 31, 2026Posted Apr 7, 2026 | Lovega LLC dba Pink Pony PeptidesOnline peptide sellerRead the letter on fda.gov | Products sold under code names. FDA quoted the product pages, which named tirzepatide and retatrutide and described fat loss and appetite effects. | |
| Mar 31, 2026Posted Apr 7, 2026 | Mile High Compounds LLCOnline peptide sellerRead the letter on fda.gov | FDA quoted "peptide cheat sheets" the company posted in an online community, which listed uses and dosing for each product, as evidence the products were meant for people. | |
| Mar 31, 2026Posted Apr 7, 2026 | PekCura LabsOnline peptide sellerRead the letter on fda.gov |
| FDA named the products by the seller's code names, plus a cagrilintide blend and bacteriostatic water. |
| Mar 31, 2026Posted Apr 7, 2026 | Prime SciencesOnline peptide sellerRead the letter on fda.gov |
| FDA identified "GLP1-R" as retatrutide and also cited the bacteriostatic water and a "Reconstitution Kit" sold with the peptides. |
| Jan 20, 2026Posted Mar 3, 2026 | GenoGenix LLCCompounderRead the letter on fda.gov | An outsourcing facility registered under section 503B. FDA said it had no approved applications for the semaglutide, tirzepatide and retatrutide it repackaged, that thymosin beta-4 is also a biological product with no biologics license, and that labels such as Epithalon lacked required compounding statements. | |
| Dec 8, 2025Posted Dec 23, 2025 | Darmerica, LLCIngredient distributorRead the letter on fda.gov |
| An ingredient (API) distributor. FDA said it sent retatrutide to pharmacies compounding under section 503A although retatrutide is not eligible, named cagrilintide, elamipretide, thymogen and other ineligible APIs it distributed, and said its hexarelin and elamipretide listings named a different active ingredient. FDA said its corrective actions on retatrutide and cagrilintide appear adequate. |
| Sep 9, 2025Posted Sep 16, 2025 | Amazing MedsTelehealth sellerRead the letter on fda.gov | FDA said the compounded retatrutide offered on the site cannot meet the conditions of section 503A or 503B, because retatrutide has no USP monograph, is in no approved drug and is on neither bulks list. It also called the claims on the site about its compounded products false or misleading. | |
| Sep 9, 2025Posted Sep 16, 2025 | ASN-LABSTelehealth sellerRead the letter on fda.gov | FDA said the compounded retatrutide offered on the site cannot meet the conditions of section 503A or 503B, because retatrutide has no USP monograph, is in no approved drug and is on neither bulks list. It also called the claims on the site about its compounded products false or misleading. | |
| Sep 9, 2025Posted Sep 16, 2025 | EA WORKS Limited Liability Company dba Trust LabsTelehealth sellerRead the letter on fda.gov | FDA said the compounded retatrutide offered on the site cannot meet the conditions of section 503A or 503B, because retatrutide has no USP monograph, is in no approved drug and is on neither bulks list. It also called the claims on the site about its compounded products false or misleading. | |
| Sep 9, 2025Posted Sep 16, 2025 | GenLabMedsTelehealth sellerRead the letter on fda.gov | FDA said the compounded retatrutide offered on the site cannot meet the conditions of section 503A or 503B, because retatrutide has no USP monograph, is in no approved drug and is on neither bulks list. It also called the claims on the site about its compounded products false or misleading. | |
| Sep 9, 2025Posted Sep 16, 2025 | GLP-1 SolutionTelehealth sellerRead the letter on fda.gov | FDA said the compounded retatrutide offered on the site cannot meet the conditions of section 503A or 503B, because retatrutide has no USP monograph, is in no approved drug and is on neither bulks list. It also called the claims on the site about its compounded products false or misleading. | |
| Sep 9, 2025Posted Sep 16, 2025 | MedClub by Dr. JennTelehealth sellerRead the letter on fda.gov | FDA said the compounded retatrutide offered on the site cannot meet the conditions of section 503A or 503B, because retatrutide has no USP monograph, is in no approved drug and is on neither bulks list. It also called the claims on the site about its compounded products false or misleading. | |
| Feb 26, 2025Posted Mar 11, 2025 | USApeptide.comOnline peptide sellerRead the letter on fda.gov | FDA listed the site's "research use only," "not for human consumption" and "lab purposes only" statements, then said the semaglutide and tirzepatide were drugs for human use. It also noted the bacteriostatic water and insulin syringes sold beside them. | |
| Dec 10, 2024Posted Dec 17, 2024 | Prime Vitality, Inc. dba Prime PeptidesOnline peptide sellerRead the letter on fda.gov | One of four letters dated December 10, 2024, the earliest in this table to name retatrutide. FDA quoted the site's claims about blood sugar, liver fat and weight loss. | |
| Dec 10, 2024Posted Dec 17, 2024 | Summit Research PeptidesOnline peptide sellerRead the letter on fda.gov | Semaglutide ("Sema"), retatrutide ("Reta"), cagrilintide, tirzepatide ("Tirz") and mazdutide, all named as unapproved new drugs. | |
| Dec 10, 2024Posted Dec 17, 2024 | SwisschemsOnline peptide sellerRead the letter on fda.gov | FDA quoted product pages that called retatrutide "a promising anti-obesity agent" and cited its phase 2 trials. | |
| Dec 10, 2024Posted Dec 17, 2024 | Xcel Research LLCOnline peptide sellerRead the letter on fda.gov | The widest list of the December 2024 letters: retatrutide, cagrilintide, a cagrilintide and semaglutide product, mazdutide, semaglutide, survodutide and sermorelin. | |
| Feb 7, 2024Posted Feb 13, 2024 | Synthetix Inc. DBA Helix Chemical SupplyOnline peptide sellerRead the letter on fda.gov | Semaglutide and tirzepatide labeled "research use only" and "not for human consumption." FDA said the website showed they were drugs for human use, unapproved and misbranded. | |
| Feb 7, 2024Posted Feb 13, 2024 | US Chem LabsOnline peptide sellerRead the letter on fda.gov | FDA reviewed the website in October 2023 and said its semaglutide, tirzepatide and Thymalin products were unapproved new drugs and misbranded. | |
| Jun 12, 2023Posted Jun 20, 2023 | Warrior Labz SARMSOnline peptide sellerRead the letter on fda.gov | A SARMs seller that also took orders for BPC-157 and TB-500. FDA quoted website claims that BPC-157 treats leaky gut, IBS and Crohn's disease. | |
| Jan 26, 2022Posted Feb 8, 2022 | Innoveix Pharmaceuticals IncCompounderRead the letter on fda.gov | FDA noted the firm's July 9, 2021 recall of compounded sermorelin/ipamorelin and AOD-9604 injections for lack of sterility assurance, and cited the unit it used to sterilize bulk drug solutions as unsuitable. | |
| Nov 10, 2021Posted Nov 16, 2021 | Advanced Nutriceuticals, LLC dba The Guyer Institute of Molecular MedicineCompounderRead the letter on fda.gov | After an inspection, FDA said cerebrolysin, thymosin alpha, thymosin beta, BPC-157, LL-37, Selank and Semax had not been nominated for the 503A bulks list, so drugs compounded from them did not qualify for the compounding exemptions. |
Recipient names are written exactly as FDA wrote them. A warning letter states FDA's view of a violation; it is not a court finding, and a company can answer it. The rules behind these letters, FDA approval and pharmacy compounding, are on the peptide legal status guide, and the difference between a pharmacy product and a research vial is on pharma vs compounded vs research peptides.
The CSV holds every letter with both dates, the recipient, FDA's subject line, the peptides named, the issues cited, the fda.gov link and the check date.
Staate. "FDA warning letters that name peptides." Last checked October 19, 2026. https://staate.co/peptides/guides/legal-status/fda-warning-letters/
<iframe src="https://staate.co/embed/fda-peptide-warning-letters/" title="FDA warning letters that name peptides, tracked by Staate" width="100%" height="640" loading="lazy" style="border:1px solid #d9e4df;border-radius:12px;max-width:100%"></iframe> <p style="font:13px/1.5 sans-serif;margin:6px 0 0">Source: <a href="https://staate.co/peptides/guides/legal-status/fda-warning-letters/">Staate, FDA warning letters that name peptides</a></p>
Retatrutide, in 21 of 29 letters, then semaglutide and tirzepatide. Since 2024 the letters have centered on weight-loss peptides. BPC-157 is named in 2 and TB-500 in 3.
Regulatory fact. A letter counts once per peptide, whether it names the drug or a code name FDA tied to it. Code names FDA did not tie to a drug are not counted.
No. In 17 of the 29 letters, FDA quoted the seller's "research use only" or "not for human consumption" wording and still called the products drugs for human use.
FDA decides what a product is for from everything the seller says and does, including the website, under its intended-use rule, 21 CFR 201.128. The letters point to product pages that describe weight loss or blood sugar results, to bacteriostatic water sold beside vials that must be mixed, and to calculators and guides for preparing an injection.
Once FDA treats a peptide as a drug for people, it is an unapproved new drug unless an FDA approval covers that exact product. Many letters add that the product is misbranded: it is sold for conditions that need a doctor, so no label could give a buyer adequate directions for use.
Six findings repeat across the letters. A letter can carry several, and the counts below come from the table.
FDA quoted the seller's "research use only" or "not for human consumption" wording, then said the website showed the products were drugs for people.
Sold beside peptides that need mixing before injection, the water itself was named as a drug. Every 2026 letter to an online seller but one names it.
From March 2026, sellers listed retatrutide as "GLP-3 RT" or "GLP-3-R" and tirzepatide as "GLP-2 T." FDA named the products by the code and, where the page said so, by the drug.
A "peptide calculator," a "peptide guide" and posted "cheat sheets" were cited as tools for preparing an injection for a person.
A compounding pharmacy, an outsourcing facility, six telehealth sellers and an ingredient distributor were told the peptides did not meet the conditions for compounding under section 503A or 503B.
Weight-loss, blood sugar, gut and prostate claims on the website were quoted as evidence of what the product was for.
Five. FDA's database holds letters dated August 24, 2026 to NuScience Peptides LLC, Peak Performance Peptides, Peptide Partners LLC, Royal Peptides LLC and TXP Innovations LLC dba Tex Peptides. Each names retatrutide and tesamorelin among other peptides, and each cites bacteriostatic water sold with the peptides.
The earlier 2026 wave was also five letters, dated March 31 and posted April 7, to Gram Peptides, Lovega LLC dba Pink Pony Peptides, Mile High Compounds LLC, PekCura Labs and Prime Sciences.
Jump to the August 24 rowsThe company is asked to answer in writing. The August 2026 letters ask for a response within 15 business days listing the steps taken to correct each violation.
All but one of the letters in this table warn that failing to fix the violations may lead to legal action, including seizure and injunction. A company that disagrees can send FDA its reasons and supporting information.
FDA may issue a close-out letter once it has checked the corrections. It will not issue one on a promise that a fix is coming. In the Darmerica letter of December 2025, FDA said the distributor's corrective actions on retatrutide and cagrilintide appeared adequate while it listed other problems.
Go to the FDA warning letters page and scroll to the searchable table.
Type a peptide name, such as retatrutide, in the search box. It searches the full letter, so expect letters that mention the word only in passing.
Most peptide letters list the Center for Drug Evaluation and Research (CDER) as the issuing office.
The subject line says "Unapproved New Drugs/Misbranded" for many unrelated products. The products named sit in the first paragraphs.
The letter date and the posting date differ by about a week, sometimes by six weeks. This table gives both.
Start at the FDA warning letters database. This table is rechecked each month and the date at the top changes when it is.
The table counts letters that name a peptide with no FDA approval for the product sold, and letters to sellers of approved GLP-1 peptides labeled for research use. As of October 19, 2026, FDA's warning letters database returns 149 letters for a search on semaglutide alone, and most of them fall outside it.
Search it yourself in the FDA warning letters database; the count changes as FDA posts letters.
Added an embeddable copy of the table for other sites, with the same rows, check date and recipient filter.
Table published with 29 letters, each read on fda.gov. FDA's database searched for every peptide profiled on staate, for "research use only" and related labels, and for "bacteriostatic water." Latest letter in scope: August 24, 2026.
Related pages: retatrutide, the BPC-157 legal status timeline, how to read a peptide COA and the peptides banned in sport and peptide warnings from the TGA, Health Canada, MHRA and Medsafe. How we label evidence: editorial policy.
We email when a warning letter wave, an FDA rule or a WADA update changes what this page says. Daily peptide brief, free, every source linked.