For millions of people living with obesity, FDA-approved GLP-1 medications have created new opportunities to improve health, reduce the burden of related chronic diseases, and receive evidence-based treatment for a condition that has too often been dismissed as a matter of willpower. At the same time, extraordinary demand for these therapies has fueled the rapid growth of compounded alternatives that are often marketed as less expensive, personalized, or equivalent substitutes. While these products may appear similar, they are fundamentally different from FDA-approved medications. This is a critical distinction that is too often overlooked.
Compounding has an important and legitimate place in medicine. A licensed pharmacist may prepare a medication for an individual patient who cannot use an approved product because of an allergy, dosage requirement, or another specific clinical need. That traditional, patient-specific practice is very different from producing and marketing compounded GLP-1 drugs on a large scale as substitutes for approved therapies.
Unlike FDA-approved medications, compounded drugs do not undergo premarket review by the U.S. Food and Drug Administration to establish their safety, effectiveness, quality, or manufacturing consistency. The FDA has issued multiple warnings about compounded GLP-1 products, citing concerns that include dosing errors, adverse events, unapproved ingredient forms, and variability in product quality. Patients deserve to understand these differences before making decisions about their treatment.
Similar language does not mean an equivalent medication
A medication marketed as “compounded semaglutide” or “compounded tirzepatide” may sound similar to an FDA-approved GLP-1 medication, but patients should not assume the products are identical. Some compounded medications have been prepared using different salt forms of semaglutide, combined with vitamins or other additives, or dispensed in concentrations that require patients to calculate and measure their own doses. These differences can introduce risks that patients may not anticipate.
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The FDA has received reports of dosing errors involving compounded injectable semaglutide, including cases that resulted in hospitalization. In some instances, patients administered substantially more medication than intended because of confusion over vial concentrations, syringes, or dosing instructions. These are not isolated technical issues, and they should concern every patient.
There have also been reports of impurities identified in compounded GLP-1 products containing added ingredients such as vitamin B12. While these products may be marketed as “personalized,” adding vitamins or other substances does not necessarily make a medication safer or more effective. In some cases, it may introduce additional variables that have not been evaluated for safety, quality, or consistency.
Patients deserve confidence in the medications they take. They should know what they are receiving, understand how it should be administered, and have transparent information about how the medication was prepared. Those conversations should take place between patients and qualified health care professionals, so treatment decisions are based on evidence, safety, and individual clinical needs.
Cost and access remain part of the problem
The growth of compounded GLP-1 drugs cannot be separated from the failures of the broader health care system. Many patients face high out-of-pocket costs, inconsistent insurance coverage, long waits to see qualified clinicians, and difficulty accessing comprehensive obesity care. Some turn to compounded products not because they reject evidence-based medicine, but because approved treatment feels financially or practically out of reach.
Those barriers are real and must be addressed. But limited access to approved medications does not make an unapproved product equivalent, nor should patients be forced to choose between receiving no care and accepting avoidable uncertainty about the contents and quality of a medication.
The solution is not to normalize mass-marketed compounded substitutes. It is to improve coverage, affordability, continuity of care, and access to qualified clinicians who understand obesity as a chronic disease. Patients need individualized evaluation, appropriate dosing, monitoring for side effects, nutritional guidance, support for preserving muscle and bone health, and ongoing assessment of overall health outcomes. The goal is not simply to lose weight. It is to safely improve health over the long term.
Clinicians can help patients navigate a confusing market
Health care professionals play an important role in helping patients distinguish between legitimate individualized compounding and large-scale marketing of unapproved products. Conversations should begin without judgment. Patients may be drawn to compounded medications because of cost, insurance coverage, convenience, or frustration with the health care system. For some, an online platform may feel more accessible and less intimidating than a traditional health care setting, particularly if they have previously experienced weight bias, felt dismissed by a provider, or delayed seeking care because of concerns about being judged. Those experiences are real and should not be overlooked. Dismissing patients’ concerns or motivations may only push them further toward less supervised sources of care rather than encouraging open, evidence-based discussions about safe and appropriate treatment options.
Clinicians have an opportunity to help patients navigate an increasingly complex treatment landscape by providing clear, evidence-based guidance. That includes explaining the differences between FDA-approved and compounded medications, discussing the benefits and limitations of each option, and ensuring patients understand the importance of receiving care from qualified health care professionals who can monitor treatment over time. Patients should also be made aware of resources that may improve access to approved therapies, including insurance appeals, financial assistance programs, and comprehensive obesity care.
Ultimately, the conversation is about more than choosing one medication over another. It is about ensuring that people living with obesity have access to safe, evidence-based, patient-centered care delivered with the same compassion and respect afforded to individuals with any other chronic disease. When patients feel supported rather than judged, they are more likely to ask questions, remain engaged in care, and make informed decisions that prioritize both their immediate and long-term health.
Innovation must not come at the expense of patient protection
We are entering one of the most promising periods in the history of obesity care. New therapies are improving health outcomes and changing how clinicians treat this complex, chronic disease. But innovation must be matched by the same commitment to patient safety, transparency, and evidence that has made these advances possible. Patients deserve to know exactly what medication they are receiving, understand how it was developed, and have confidence that treatment decisions are grounded in sound science, not marketing claims.
Compounding should continue to serve its intended purpose: meeting the individualized needs of patients when an FDA-approved option is not appropriate or available. It should not become a substitute for approved therapies or a parallel marketplace built on confusion about product equivalency. The future of obesity care depends not only on expanding access to effective treatments, but on ensuring those treatments are delivered through evidence-based, patient-centered care that prioritizes safety, trust, and long-term health.
This essay is cited in the KevinMD record on GLP-1 drugs.
Marc-André Cornier, MD, FTOS, is the past president of The Obesity Society.
The Obesity Society (TOS) is the leading scientific organization dedicated to advancing the understanding, prevention, and treatment of obesity. Through research, education, and evidence-based advocacy, TOS promotes a comprehensive and science-driven approach to addressing obesity as a serious, chronic, and treatable disease. Its members include scientists, clinicians, policymakers, and other professionals working to improve health outcomes and reduce the global impact of obesity.
TOS publishes Obesity, its flagship peer-reviewed scientific journal. Learn more at obesity.org, and follow the Society on Instagram, X, and YouTube.
