This past June, the FDA sent out 25 warning letters to telehealth companies selling compounded semaglutide and tirzepatide.This is the third enforcement wave in less than a year, following a batch of 30 letters in March, and more than 55 letters in September 2025.
Three waves of warnings in less than twelve months tells us a few things: this is a pervasive issue; the first two rounds of warnings didn’t fix the problem, and the FDA is determined to address this issue.
The targets aren’t backwater dispensaries. They are polished, direct-to-consumer (DTC) telehealth marketing companies with slick websites.
This story is often framed simply as “FDA crackdowns on counterfeit weight-loss drugs.” But from a pharmacy and regulatory perspective, the real issue is more subtle and is clearly having an effect: the deliberate creation of a “misleading net impression” that compounded peptides are equivalent from a safety and effectiveness perspective to FDA-evaluated and approved generic drugs. They are not.
What is a “compounded” drug?
I’ve discussed compounding before. Ozempic, Wegovy, Mounjaro, and Zepbound are FDA-approved medicines.These products underwent clinical testing to evaluate their safety and effectiveness, and the FDA reviewed the clinical, safety, quality, and manufacturing data. FDA approval also means that the manufacturing facilities and processes meet strict regulatory standards, designed to ensure that products are consistently manufactured, and meet established specifications for quality, purity, strength, and potency. The FDA also reviews evidence demonstrating that the commercially manufactured product is comparable to the product used in clinical trials (which may have been made under very different circumstances). Together, these requirements provide confidence that the evidence from those clinical trials is directly relevant to the marketed product. Clinicians and patients can therefore expect similar benefits and risks to those that were observed in the research, while recognizing that real-world effects may differ.
A compounded version of semaglutide or tirzepatide may contain the same active ingredient as the approved drug, but it is not the drug that was reviewed and approved by the FDA. The FDA does not independently evaluate specific compounded products for safety, effectiveness, manufacturing quality, or consistency. This does not mean that a compounded product is unsafe, but it does mean that patients must rely on the standards and practices of the compounder rather than the extensive review and oversight that support an FDA-approved medicine.
The widespread compounding of semaglutide and tirzepatide in the past was permissible under FDA drug shortage provisions. Under U.S. law, “503A” pharmacies may compound patient-specific prescriptions, while “503B” refers to outsourcing facilities permitted to compound medications in larger quantities for healthcare providers and institutions. Under certain circumstances, both may compound products that contain the same active ingredient as FDA-approved drugs when those drugs appear on the FDA drug shortage list. Semaglutide and tirzepatide were compounded on a large scale because Wegovy, Ozempic, Zepbound, and Mounjaro faced supply shortages due to overwhelming demand. These provisions were intended as a temporary response to supply disruptions, not as a means for patent circumvention and production of approved medicines.
It’s notable that the FDA announced on May 1, 2026, that it proposes not to include semaglutide, tirzepatide, and liraglutide on the 503B Bulks List, concluding that the evidence did not demonstrate a clinical need for outsourcing facilities to compound these drugs from bulk active ingredients. (The public comment period has been extended to July 30, 2026.) This remains a proposal rather than a final determination, but if finalized, it will eliminate the principal 503B bulk-compounding pathway that has supported much of the large-scale telehealth GLP-1 compounding market.
The FDA has taken an even stricter position with retatrutide and cagrilintide. Neither drug has been approved by the FDA, and neither appears on the agency’s drug shortage list. A product that isn’t approved cannot be in short commercial supply, so there is no regulatory pathway for routine compounding of these products. Unlike semaglutide or tirzepatide, there is no FDA-approved reference product whose safety, effectiveness, manufacturing quality, and labeling have been reviewed by regulators. Products marketed as compounded retatrutide or cagrilintide are consequently fully outside this framework for approved prescription drugs and shortages.
The “misleading net impression” problem
The legal hook FDA is using across all three enforcement waves is a longstanding advertising framework called misleading net impression. In short, you can’t build a misleading claim out of technically true pieces. If your website says “FDA-approved active ingredient,” shows a product photo with your own company’s name on the label, and describes your product’s outcomes as “the same” as the branded drug, none of those statements individually needs to be false for the overall impression to be false. Consumers will be left with the impression they’re getting a product that’s FDA approved, when that’s not the case.
One letter in June 2026 flagged marketing language describing a “body safe vitamin such as B12” added to a compounded semaglutide product, language that implies a formulation decision backed by some sort of clinical rationale. Others flagged product labels bearing the marketing company’s own name or clinic branding, which under FDA’s labeling rules is itself a representation that the named party is the manufacturer, when in fact they’re simply a marketer, sourcing product from a compounding pharmacy the consumer doesn’t see named.
The Surveillance Gap
As of May 2026, the FDA had logged more than 1,700 adverse events tied to compounded semaglutide and tirzepatide. As we don’t have a reliable denominator, there’s no way to compare it against an adverse event incidence rate for the FDA-approved products. With compounded products there is no manufacturer-mandated monitoring and reporting obligations, so any reporting is patients and prescribers doing it voluntarily. What this signals is that drug products with effectively no formal post-marketing monitoring have still generated over 1,700 reports. It’s certainly a fraction of the actual adverse events – there is no way to know what the actual number is.
The Exception that Became the Business Model
There is a legitimate, narrow purpose for compounding these drugs: a genuine, FDA-recognized shortage, filled temporarily by a licensed 503A or 503B facility compounding a chemically identical product under quality standards, with clarity that the product is not the same as an approved drug. That is not what these companies appear to be marketing. It’s access, convenience, and a lower price point, wrapped in the apparent veneer of FDA oversight, sold to consumers who may not appreciate the difference between “compounded because of a legally recognized shortage” and “compounded because it’s profitable and enforcement has been limited.” Three enforcement waves in under a year suggests FDA has noticed the gap between those two things, and they are determined to close it.