The U.S. Food and Drug Administration (FDA) has issued a response following multiple adverse events linked to unapproved weight loss drugs. Dosing errors related to unapproved drugs have resulted in several hospitalizations, including a few fatalities. Drugs lacking FDA approval have not been reviewed by the agency for safety, effectiveness, or quality—unlike FDA-approved medications that meet strict regulatory standards. In an effort to better educate and inform the public, the FDA issued a statement to address its concerns over the use of unapproved Glucagon-like peptide-1 (GLP-1) agonists, the active component of popular weight loss drugs like Ozempic and Wegovy. Both drugs utilize a GLP-1 peptide but are FDA approved for different uses. Ozempic is approved for the management of type 2 diabetes and blood sugar levels; Wegovy is approved to treat obesity.
Owing to their popularity and high cost, some patients and healthcare professionals have sought out more affordable alternatives. An entire international medical tourism industry has arisen in countries (like Mexico) where the popular weight loss drugs may be purchased at a significant discount. However, purchasing unapproved drugs poses serious risks and can even be fatal. In November 2024 The Times reported ten deaths and 100 hospitalizations due to the use of off-brand versions of Ozempic and Wegovy.1 According to the article, “In October, Novo Nordisk asked the FDA to ban off-brand semaglutide products, arguing that the active ingredient was too complex to manufacture safely in the correct dosages. The agency said it had received reports of events “requiring hospitalization, that may be related to dosing errors associated with compounded injectable semaglutide products”, and that it was reviewing Novo Nordisk’s request.”
The compounding industry issued a counter-response to Norvo Nordisk’s ban request. Chief executive of the Alliance for Pharmacy Compounding, Scott Brunner, objected claiming it “lacked context.” This year, however, the FDA unequivocally declared its official stance on compounded products. In the past, compounded weight loss drugs were permitted as there was a shortage of FDA approved versions. As supply has met demand, the FDA officially declared an end to the semaglutide shortage. Weight-loss compound facilities were given between 60 and 90 calendar days to completely cease production2 — 503A compounders have until April 22 and 503B compounders have until May 22, respectively.
To underscore their concerns surrounding the unauthorized use of unapproved weight loss drugs, the FDA also issued a statement. Entitled “FDA’s Concerns with Unapproved GLP-1 Drugs Used for Weight Loss,” it provides patients and providers with some of the background, issues and recommendations3. It includes some helpful recommendations for healthcare providers and patients:
FDA’s Concerns with Unapproved GLP-1 Drugs
FDA recommendations for patients
- Patients should obtain a prescription from their doctor and fill the prescription at a state-licensed pharmacy.
- Visit FDA’s BeSafeRx campaign for resources to safely buy prescription medicines online.
- Talk to your doctor if you have questions about your medicines.
Concerns with compounded versions of these drugs
A compounded drug might be appropriate if a patient’s medical need cannot be met by an FDA-approved drug, or the FDA-approved drug is not commercially available. However, compounded drugs are not FDA approved. This means the agency does not review compounded drugs for safety, effectiveness or quality before they are marketed.
The agency has identified some areas of concern for compounded GLP-1 drugs. FDA is working with its state regulatory partners and will continue to communicate with compounders regarding these concerns.
Dosing concerns with compounded semaglutide and tirzepatide
FDA received multiple reports of adverse events, some requiring hospitalization, that may be related to dosing errors associated with compounded injectable semaglutide products. These dosing errors resulted from patients measuring and self-administering incorrect doses of the drug, and in some cases, health care professionals miscalculating doses of the drug.
Additionally, the agency has received adverse event reports that may be related to patients prescribed compounded semaglutide or tirzepatide products in doses beyond what is in the FDA-approved drug label. This could mean using more product in a single dose, taking doses more frequently or increasing the amount more quickly (titration schedule). Some of the adverse events are serious and some patients reported seeking medical attention for their symptoms, including nausea, vomiting, diarrhea, abdominal pain and constipation.
Health care providers should be vigilant when prescribing compounded semaglutide or tirzepatide products and determining appropriate doses and titration and dosing schedules for patients. The agency also encourages patients to talk with their health care provider or compounder about how to measure and administer the intended dose of compounded semaglutide or tirzepatide.
Retatrutide cannot be used in compounding
Retatrutide cannot be used in compounding under federal law. Additionally, it is not a component of an FDA-approved drug and has not been found safe and effective for any condition.
Salt forms should not be used to compound semaglutide
The agency is aware that some semaglutide products sold by compounders may be the salt forms. These salt forms, including semaglutide sodium and semaglutide acetate, are different active ingredients than are used in the approved drugs. The agency does not have information on whether these salts have the same chemical and pharmacologic properties as the active ingredient in the approved drug, and we are not aware of any lawful basis for their use in compounding.
Adverse events related to compounded versions of semaglutide and tirzepatide
FDA has received reports of adverse events related to compounded versions of semaglutide and tirzepatide. However, federal law does not require state-licensed pharmacies that are not outsourcing facilities to submit adverse events to FDA so it is likely that adverse events from compounded versions of these drugs are underreported. Many of the adverse events reported for compounded products appear to be consistent with adverse events related to the FDA-approved versions of these products.
As of Feb. 28, 2025, the FDA has received:
- more than 455 reports of adverse events with compounded semaglutide.
- more than 320 reports of adverse events with compounded tirzepatide.
It is not always possible to determine if the adverse event directly resulted from use of the drug or if other factors may have contributed to these adverse events.
Illegally marketed versions of these drugs
Counterfeit Ozempic
FDA is aware of counterfeit Ozempic marketed in the U.S. Counterfeit drugs claim to be authentic, but could contain the wrong ingredients, contain too little, too much or no active ingredient at all or other harmful ingredients, and are illegal.
The agency investigates reports of suspected counterfeit drugs to determine the public health risks and the appropriate regulatory response. FDA remains vigilant in protecting the U.S. drug supply from these threats.
Illegal online sales of these drugs
FDA monitors the internet for fraudulent or unapproved drugs and has issued warning letters to stop the distribution of illegally marketed semaglutide and tirzepatide. These illegally marketed drugs:
- may be counterfeit
- could contain the wrong ingredients or harmful ingredients
- could contain too little, too much or no active ingredient at all
The agency urges consumers to be vigilant when purchasing drugs online and only purchase from state-licensed pharmacies.
Versions sold falsely for research purposes or not for human consumption
FDA has warned companies that have illegally sold unapproved drugs containing semaglutide, tirzepatide or retatrutide that are falsely labeled “for research purposes” or “not for human consumption.” These products have been sold directly to consumers for human use with dosing instructions. The agency urges consumers not to purchase these products which are of unknown quality and may be harmful to their health.
Reporting issues to FDA
FDA encourages health care professionals, patients and compounders to report adverse events or quality problems with these or any medications to FDA’s MedWatch Adverse Event Reporting program:
- Complete and submit the report online, or
- Download and complete the form, then submit it via fax at 1-800-FDA-0178.
You also may contact the CDER Division of Drug Information at druginfo@fda.hhs.gov or 855-543-3784.
Finally, the FDA offers and encourages individuals to report adverse events and quality issues directly to them — via an online form, direct phone call or email (see above).
- https://www.thetimes.com/life-style/health-fitness/article/ozempic-fake-side-effects-weight-loss-gf8djkgws ↩︎
- https://www.pharmacypracticenews.com/PrintArticle/76337 ↩︎
- https://www.fda.gov/drugs/postmarket-drug-safety-information-patients-and-providers/fdas-concerns-unapproved-glp-1-drugs-used-weight-loss ↩︎