How to Vet a Compounded GLP-1 Provider Using the FDA's Own Warning-Letter Checklist
Vet a compounded semaglutide provider using the four claim patterns FDA cited across its 2026 warning letters to 55 telehealth marketers.
How to Vet a Compounded GLP-1 Provider Using the FDA's Own Warning-Letter Checklist **The most reliable way to judge whether a compounded semaglutide or tirzepatide provider is operating legitimately is to read its own website against the four claim patterns the FDA cited across its 2026 warning letters: claiming the compounded product is equivalent to or the same as the approved drug, implying FDA approval or FDA evaluation of safety and effectiveness, describing the compounding pharmacy or facility as "FDA-approved" or "FDA-licensed," and using private-label branding that obscures which entity actually compounded the product. FDA posted 25 such letters on June 16, 2026, issued June 8 by the Center for Drug Evaluation and Research under the subject line "False & Misleading Claims/Misbranded (Telehealth)," following 30 announced on March 3, 2026 and more than 50 sent to GLP-1 compounders and manufacturers in September 2025. None of these four checks requires clinical judgment, because each one is about what a company says in public and who actually produced the product, which makes them questions you can ask, answer, and document before you ever discuss anything with your prescriber.** Two enforcement waves in 2026 have effectively published a rubric. When a regulator sends the same objections to 55 companies inside four months, it is telling you which statements it considers indefensible, and it is doing so in writing that anyone can read. That rubric happens to be unusually useful to a patient or a coach, because it does not ask you to evaluate a molecule, a dose, or a clinical decision. It asks you to compare a company's marketing copy against a short list of things a compounded product legally cannot claim, and to establish who actually made what you are holding. This article walks through that checklist, explains what each pattern means, and covers what is worth writing down. MyProtocolStack is a tracking and education tool. Nothing here diagnoses, treats, or tells you to start, stop, or change any medication. Those decisions belong with your licensed clinician.
What the FDA Actually Sent, and When
The timeline matters because it shows a pattern rather than a one-off action.
Each company in the June wave was given 15 business days from receipt to respond. Notably, the response was not simply a request to take down bad copy. Recipients were asked to identify the entity that actually produced the compounded drug and to supply representative samples of the product labeling, alongside addressing or confirming removal of the claims at issue. That detail is the tell. The agency wanted to know who made it, not only what was said about it, which is exactly the question a patient is least likely to have asked.
A warning letter is an allegation of violation, not a court finding, and companies do respond and correct. So the presence of a company on a list is not a verdict. What the letters give you is something more durable than a blacklist: a description of the specific statements FDA considers misleading, which you can apply to any provider, including ones that have never received a letter.
The Four Claim Patterns, and How to Check Each One
Here is the checklist in the form you can actually run. Every one of these is answered by reading a website, a label, or a support email reply. None requires a clinician.
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Pattern 3 is worth dwelling on because it is the one most people cannot evaluate from intuition. FDA does not grant approval or licensure to compounding pharmacies or to their compounded products. That authorization does not exist. So a site claiming it is not overstating a real credential, it is describing something the agency does not issue at all. Pharmacies are licensed by states. Outsourcing facilities register with FDA under section 503B, and FDA is explicit that registration means only that the agency received the information required to register the facility. In FDA's own words, registration does not mean the facility is making FDA-approved drugs, and it does not mean the facility has been found to comply with current good manufacturing practice requirements. Any site that blurs those distinctions has told you something useful about its standards.
Pattern 4 is the one FDA appears to care most about operationally, given that the letters asked recipients to identify the actual drug producer. Private labeling is legal in many contexts. The problem the letters describe is labeling that identifies the telehealth company as the compounder when it was not. If you cannot get a straight answer to "who compounded this," you have learned something, and it is worth logging that the question went unanswered. Our guide on [how to find a reputable compounding pharmacy](/blog/how-to-find-compounding-pharmacy) covers the credential side of that question in more depth.
### The Fifth Check: Added Ingredients and the "Personalized" Claim
There is a fifth thing worth checking that sits slightly outside the four claim patterns. FDA has scrutinized pharmacies that add vitamins or other ingredients to a compounded GLP-1 and market the result as "personalized." Under the rules against compounding what is essentially a copy of a commercially available drug, FDA has indicated it may treat a product combining semaglutide with another active ingredient such as vitamin B12 as essentially a copy. The 503A exception turns on a change made for an identified patient whose medical needs cannot be met by the approved product, documented on the prescription and medically justified for that specific patient rather than chosen for convenience or cost. A benefit that could be obtained by giving the approved drug and the additive separately does not, in that framing, convert a copy into a personalized preparation.
There is also a chemistry question here that is genuinely unsettled, and it is worth being careful about who reported what. On March 12, 2026, Eli Lilly, which manufactures branded tirzepatide, published an open letter reporting that its own laboratory testing of compounded tirzepatide samples, obtained from compounding pharmacies, med spas, and telehealth sellers, found an impurity formed by a chemical reaction between tirzepatide and vitamin B12, producing a substance not present in the FDA-approved drug. Lilly stated that the effects of that substance in humans are not known, including its toxicity, its potential for immune reactions, and how it is absorbed and eliminated, and noted that tirzepatide has never been studied in combination with B12. Stanford Medicine has since described the underlying finding as replicated laboratory work.
Two caveats belong with that. First, this is laboratory chemical analysis, not a human clinical trial. No human outcome data establishes what the finding means for people, and Lilly itself said as much. Second, the Alliance for Pharmacy Compounding, the compounding industry's trade group, publicly disputed the completeness of Lilly's disclosure, questioning where the samples came from, how they were stored and handled, and how "significant levels" was defined, and noting that Lilly competes commercially with compounded versions of its own drug. Both of those things can be true at once, and neither resolves the question. The practical takeaway is not alarm, it is documentation: if your formulation contains anything beyond the GLP-1 itself, that belongs in your record and in your clinician's, precisely because the evidence base is thin.
So the fifth question is simply: does my product contain added ingredients, and if so, what are they? That is a factual question with a written answer.
Why This Is Worth an Hour of Your Time Right Now
A Gallup poll released July 7, 2026, based on 5,065 US adults surveyed May 28 to June 5, 2026, found that 11% of US adults currently take a GLP-1 medication for weight loss, up from 3% in 2024. Among those users, 68% reported taking a name-brand product, 19% reported taking a compounded or custom-mixed version, and 12% were unsure which they were taking. Roughly one in five GLP-1 users is therefore in the category these warning letters concern, and among people who had switched from a name-brand product to a compounded one, 66% cited cost or insurance coverage as the reason, about twice the rate seen among those switching in the opposite direction.
The regulatory ground is also moving underneath that group. On April 30, 2026, FDA proposed leaving semaglutide, tirzepatide, and liraglutide off the 503B Bulks List, a change that would end large-scale outsourcing-facility compounding of these drugs from bulk substances if finalized. The public comment period closed July 30, 2026, and no final decision has been announced. We covered the mechanics and status of that proposal in our piece on [what the 503B decision means](/blog/compounded-glp1-503b-ban-2026). Separately, the advertising side has its own precedent, which we covered in [compounded GLP-1 advertising rules for clinics](/blog/compounded-glp1-advertising-rules-2026). Neither of those articles is contradicted by anything here. This one adds the consumer-facing checklist that sits on top of both.
For Coaches: This Is a Documentation Conversation
Health coaches, trainers, and non-clinical practitioners are routinely put in an awkward position when a client mentions a compounded GLP-1. The instinct is to say nothing, because anything that sounds like advice about a medication is outside scope. That instinct is correct about the medication and wrong about the paperwork.
Running a client's provider through these four patterns involves no medical or legal judgment whatsoever. You are reading a company's public marketing copy and comparing it to a published list of statements a regulator has objected to. You are asking who manufactured a product. Neither is diagnosis, treatment, prescribing, or legal opinion. It is the same category of work as helping someone confirm whether their lab used the same assay across two draws.
What makes it useful rather than merely tidy is that it produces three durable records:
If any of the four patterns turns up on the provider's site, the appropriate move is not to tell the client to stop anything. It is to write down what you found and route it to the prescribing clinician, who is the person qualified to weigh it. A coach who hands a physician a clean one-page record of source, compounder, and formulation has made that physician's job materially easier without stepping an inch outside scope.
What to Track
Vetting is a one-time task per provider. The tracking around it is ongoing, and it splits into two categories: provenance fields and biomarkers. Provenance is the part almost nobody logs and the part that becomes impossible to reconstruct later.
Provenance fields worth recording at the start and any time a provider or formulation changes:
On the biomarker side, the panel people commonly track on GLP-1 therapy does not change based on where the product came from, but a provenance change is a sensible moment to make sure the record is current. The markers most often discussed in this context include [HbA1c](/biomarkers/hba1c), [fasting glucose](/biomarkers/fasting-glucose), [fasting insulin](/biomarkers/fasting-insulin), [triglycerides](/biomarkers/triglycerides), [HDL-C](/biomarkers/hdl-c), and liver enzymes such as [ALT](/biomarkers/alt) and [AST](/biomarkers/ast). Our [GLP-1 lab monitoring panel](/blog/glp1-lab-monitoring-panel) covers the typical baseline and follow-up cadence in detail. Body composition and weight trend data are commonly logged alongside these. None of this is a recommendation to test, and what any value means for you is your clinician's determination.
[Keep your source, compounder, formulation, and lab trend in one organized record with MyProtocolStack.](/auth/login?mode=signup)
The reason to keep provenance and biomarkers in the same place is continuity. If a formulation changes, if a provider is one of the companies that received a letter and revised its practices, or if you switch sources for cost reasons, the only way to see whether anything in your own data shifted around that date is to have the date written down next to the numbers. That is a record-keeping problem, and it is the one part of this that a tracking tool genuinely solves.
The Honest Limits of This Checklist
Four patterns read off a website will not tell you whether a product is sterile, correctly dosed, or accurately potent. Those are questions of manufacturing quality that no consumer can assess from marketing copy. FDA has separately flagged dosing and administration errors as a major source of reported adverse events involving compounded GLP-1s, describing reports of patients inadvertently drawing five to 20 times the intended dose from multidose vials, in some cases because dosing instructions were written in units rather than in milligrams or milliliters. That is a risk a website audit cannot touch, and it is a question for the prescriber and pharmacist who wrote and filled the instructions.
What the checklist does is narrower and still valuable. A company willing to tell you plainly that its product is not FDA-approved, that its pharmacy is state-licensed rather than FDA-licensed, and exactly which facility compounded your vial is demonstrating a posture toward accuracy. A company that fails all four is demonstrating a different one. That is a signal about candor, not a certificate of quality, and it should be treated as the first filter rather than the last word. The last word belongs to the clinician who is actually responsible for your care.
Frequently Asked Questions
How can I tell if a compounded semaglutide provider is legitimate?
Read the provider's own website against the four claim patterns FDA cited across its 2026 warning letters: claiming equivalence or sameness with the approved drug, implying FDA approval or FDA evaluation of safety and effectiveness, describing the compounding pharmacy or facility as "FDA-approved" or "FDA-licensed," and private-label branding that obscures which entity actually compounded the product. Then ask directly, in writing, which pharmacy or outsourcing facility produced your product. All four checks are about public marketing copy and provenance, so none requires clinical judgment. A provider that fails several is showing you its posture toward accuracy, though a clean result is a first filter, not proof of product quality, and any decision about the medication itself belongs with your prescribing clinician.
How many FDA warning letters have gone to GLP-1 compounders and telehealth marketers?
There have been three documented waves. In September 2025, FDA sent more than 50 warning letters to US and international companies compounding or manufacturing semaglutide and tirzepatide, most dated September 9, 2025. On March 3, 2026, FDA made public 30 letters to telehealth companies, dated February 20, 2026, over illegal marketing of compounded GLP-1s. On June 16, 2026, FDA posted 25 more, issued June 8, 2026 by the Center for Drug Evaluation and Research under the subject line "False & Misleading Claims/Misbranded (Telehealth)." Recipients of the June letters were given 15 business days from receipt to respond, identify the entity that actually produced the drug, and supply representative labeling.
Can a compounding pharmacy be "FDA-approved" or "FDA-licensed"?
No. FDA does not grant approval or licensure to compounding pharmacies, to outsourcing facilities, or to their compounded products, which is why the agency cited that language as misleading. Compounding pharmacies are licensed by states. Outsourcing facilities register with FDA under section 503B, and FDA states that registration means only that it received the information required to register the facility, not that the facility makes FDA-approved drugs or has been found to comply with current good manufacturing practice requirements. A site claiming FDA approval or licensure for a facility is describing an authorization that does not exist. Accurate descriptions reference state licensure or 503B registration instead.
Does adding vitamin B12 make a compounded GLP-1 "personalized"?
Not on its own. FDA has indicated it may treat a compounded product combining semaglutide with another active ingredient such as vitamin B12 as essentially a copy of a commercially available drug, and the 503A exception turns on a change made for an identified patient whose medical needs cannot be met by the approved product, documented and medically justified for that patient rather than chosen for marketing, convenience, or cost. Separately, Eli Lilly published an open letter on March 12, 2026 reporting that its own testing of compounded tirzepatide samples found an impurity formed by a chemical reaction with B12, and stated that the effects in humans are not known. The compounding industry's trade group disputed the completeness of that disclosure and noted Lilly's commercial interest. That is laboratory chemistry, not human clinical trial evidence, which is exactly why any added ingredients belong in your record and in your clinician's.
Can a health coach help a client vet a compounded GLP-1 provider?
Yes, because the checklist involves no medical or legal judgment. Comparing a company's public marketing copy to a published list of statements a regulator has objected to, and asking who manufactured a product, is documentation work rather than diagnosis, treatment, prescribing, or legal opinion. It produces three records worth keeping: the source the client orders from, the named entity that actually compounded the product, and whether the formulation contains added ingredients. If a pattern turns up, the appropriate step is to document it and route it to the prescribing clinician, never to advise a client to start, stop, or change a medication.
Sources
1. U.S. Food and Drug Administration, press announcement: "FDA Warns 30 Telehealth Companies Against Illegal Marketing of Compounded GLP-1s," March 3, 2026. https://www.fda.gov/news-events/press-announcements/fda-warns-30-telehealth-companies-against-illegal-marketing-compounded-glp-1s
2. U.S. Food and Drug Administration, "Questions and Answers: Outsourcing Facility Registration." https://www.fda.gov/drugs/human-drug-compounding/questions-and-answers-outsourcing-facility-registration
3. U.S. Food and Drug Administration, press announcement: "FDA Proposes to Exclude Semaglutide, Tirzepatide, and Liraglutide from the 503B Bulks List," April 30, 2026. https://www.fda.gov/news-events/press-announcements/fda-proposes-exclude-semaglutide-tirzepatide-and-liraglutide-503b-bulks-list
4. McDermott Will and Emery, "FDA takes aim at misleading online claims for compounded GLP-1 drugs." https://www.mcdermottlaw.com/insights/fda-takes-aim-at-misleading-online-claims-for-compounded-glp-1-drugs/
5. Sheppard Mullin, "FDA's Focus Returns to Compounding and Telehealth: Another Wave of Warning Letters." https://www.sheppard.com/insights/blogs/fdas-focus-returns-to-compounding-and-telehealth-another-wave-of-warning-letters
6. Foley and Lardner LLP, "GLP-1 Compliance: FDA Targets Telehealth Marketing in 30 New Warning Letters." https://www.foley.com/p/102mmr0/glp1-compliance-fda-targets-telehealth-marketing-in-30-new-warning-letters/
7. Venable LLP, "FDA's Latest GLP-1 Crackdown: What Compounders Need to Know," March 2026. https://www.venable.com/insights/publications/2026/03/fdas-latest-glp-1-crackdown-what-compounders
8. Wilson Sonsini, "FDA Sends Warning Letters to More Than 50 GLP-1 Compounders and Manufacturers." https://www.wsgr.com/en/insights/fda-sends-warning-letters-to-more-than-50-glp-1-compounders-and-manufacturers.html
9. Eli Lilly and Company, "An open letter from Eli Lilly and Company warning of potential patient safety risks associated with tirzepatide compounded with vitamin B12," March 12, 2026. https://investor.lilly.com/news-releases/news-release-details/open-letter-eli-lilly-and-company-warning-potential-patient
10. Alliance for Pharmacy Compounding, "Lilly's B12 bombshell, or is it?" https://a4pc.org/news/lillys-b12-bombshell-or-is-it
11. Stanford Medicine, "Compounded GLP-1s: Why doctors worry and the FDA is cracking down," July 2026. https://med.stanford.edu/news/insights/2026/07/glp1s-compounded-why-doctors-worry-about-safety.html
12. Gallup, "In U.S., GLP-1 Usage Reaches New High," July 7, 2026. https://news.gallup.com/poll/712157/glp-usage-reaches-new-high.aspx
13. Forbes, "11% Of Americans Now Take GLP-1 Drugs As Obesity Rate Declines, Poll Finds," July 7, 2026. https://www.forbes.com/sites/zacharyfolk/2026/07/07/11-of-americans-now-take-glp-1-drugs-as-obesity-rate-declines-poll-finds/
*MyProtocolStack is a tracking and education tool, not medical advice, diagnosis, or treatment, and you should always consult a qualified healthcare professional before making any changes to your health protocol.*
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