Compounded versus brand-name medicines

What each term means

• FDA-approved product: the manufacturer submitted data, the FDA reviewed it, and the product is sold under a label that states its dose, uses and warnings. Wegovy and Zepbound are examples, and their labels are on DailyMed.
• Compounded drug: a medicine a pharmacist or physician makes or changes for one patient. The FDA describes the idea as creating a medication tailored to an individual patient, for example a dye-free version for someone with a dye allergy.
• Not the same thing: the FDA says compounded drugs are not FDA-approved, and it does not verify their safety, effectiveness or quality before they are marketed.
• Generic: a different category. Generics are approved by the FDA as copies of approved drugs. Compounded drugs have no such approval.

Why compounded versions became common

The FDA lists drugs in shortage. When a drug is on that list, the law lets compounders make versions of it under certain conditions. Tirzepatide and semaglutide were in shortage for much of 2022 to 2024, and many people used compounded versions during that time.

A 2025 study of a large primary-care dataset found documented compounded GLP-1 use in about 8% of patients, while surveys suggested far more people were using them. The gap suggests that clinicians often do not know when a patient is on a compounded product, which is one reason to tell your clinician what you take.

What changed when the shortages ended

According to the FDA, the tirzepatide shortage was resolved in late 2024 and the semaglutide shortage on February 21, 2025. The FDA then set end dates for its temporary leniency toward compounders. For large outsourcing facilities (called 503B facilities) the dates were March 19, 2025 for tirzepatide and May 22, 2025 for semaglutide.

Pharmacies that compound for individual patients (called 503A pharmacies) can still make a drug for a specific patient on a prescription. The FDA says compounding is meant for patients whose medical needs cannot be met by an approved drug, and it still takes action against substandard or unsafe products. The page What a 503A pharmacy is goes deeper on how these pharmacies work and why prices differ.

A law-firm summary dated September 10, 2026 reports that a federal appeals court upheld the FDA decisions that the shortages had ended. The decision is unpublished, and the Atlas has not read it directly. Rules and court cases in this area keep moving, so check current sources.

What the FDA says about the risks

The FDA page on unapproved GLP-1 drugs makes several points. In plain terms:

• Adverse events: as of May 31, 2026 the FDA had received 990 reports for compounded semaglutide and more than 730 for compounded tirzepatide. It says these are likely underreported.
• Dosing errors: some reports involved patients measuring doses wrongly and some involved clinicians miscalculating doses. Some led to hospitalization.
• Doses above the label: some patients were prescribed larger or more frequent doses, or faster dose increases, than the approved label describes. Reported symptoms included nausea, vomiting, diarrhea, abdominal pain and constipation.
• Different ingredient forms: the FDA says semaglutide sodium and semaglutide acetate are not the same active ingredient as in the approved drugs, and it is not aware of a lawful basis for compounding with them.
• Retatrutide and cagrilintide: the FDA says these cannot be used in compounding under federal law.
• Counterfeit and mislabeled products: the FDA reports counterfeit Ozempic in the U.S. supply, and compounded labels that name pharmacies that do not exist or did not make the product.
• "For research" products: the FDA says semaglutide, tirzepatide, retatrutide, survodutide and mazdutide have been sold as "for research purposes" or "not for human consumption" while being marketed for human use, and it advises against buying them.

What is different in practice

Approved products come with a label, a fixed set of dose strengths and a manufacturer who is responsible for them. Many come in pens. Compounded injectables are often supplied in vials, and the FDA has linked some dosing errors to measuring. If your prescriber supplies anything that needs measuring, ask them to teach it to you directly. The Atlas does not give mixing or measuring instructions.

The FDA also says multi-dose vials should be discarded 28 days after first use, and that injectable GLP-1 products that arrive warm or without enough refrigeration should not be used.

The approved labels describe results from trials of the approved products. Those results do not automatically carry over to a compounded version, because no one has shown it is the same.

Red flags the FDA lists

• Deep discounts that look too good to be true.
• No licensed clinician reviewing your health history.
• Label errors or a pharmacy name you cannot confirm.
• A product sold "for research" or "not for human consumption" but marketed to you.
• The FDA says to buy only from state-licensed pharmacies, and to report problems to its MedWatch program.

Questions to ask

• Is the product you are prescribing me FDA-approved or compounded?
• If it is compounded, which pharmacy makes it, and is that pharmacy licensed in my state?
• Why is a compounded version needed for me instead of the approved product?
• What dose strength will I receive, and does it match the approved label?
• Who will show me how to take it, and who do I call if something goes wrong?
• What happens to my plan if the rules or the supply change?

What is still unknown

• The Atlas found no trial that tested a compounded GLP-1 against the approved product.
• Adverse event counts to the FDA come from voluntary reports. They cannot tell you how common a problem is.
• Compounding rules and court cases are still changing, and what is allowed may differ by state.
• The Atlas has not read the appeals court decision itself and relies on a law-firm summary of it.