Compounded Semaglutide vs Ozempic and Wegovy: What Changed After the Shortage

The main difference in compounded semaglutide vs Ozempic and Wegovy is regulatory: the brand products are FDA-approved and made under federal manufacturing rules, while compounded versions are not FDA-approved and were never reviewed for safety, effectiveness or quality. Compounders were allowed to make copies on a large scale only while semaglutide was on the FDA drug shortage list. The FDA declared that shortage resolved on February 21, 2025, and the grace periods that followed have ended.

That does not mean every compounded semaglutide product is now illegal, but the room left for lawful copies is narrow. Here is what changed, what the FDA has said since, and what to look for if you are being offered a compounded version today.

Why compounded semaglutide existed in the first place

Compounding is the preparation of a medicine by a pharmacy for a patient whose needs an approved product cannot meet. Federal law generally limits compounders from making drugs that are “essentially copies” of approved or commercially available products. The exception that mattered here is a drug shortage: a drug on the FDA shortage list is not treated as “commercially available,” so copies are permitted while the shortage lasts.

According to the FDA’s February 21, 2025 order, the semaglutide injection shortage began in March 2022 for Wegovy and August 2022 for Ozempic. Compounded copies filled that gap for more than two years, sold through pharmacies, clinics and telehealth services.

Two kinds of compounder

The law recognises two types. Section 503A covers state-licensed pharmacies and physicians compounding for individual patients on a prescription. Section 503B covers “outsourcing facilities,” which register with the FDA. In the same order, the FDA explained that 503B facilities are subject to current good manufacturing practice (CGMP) requirements, FDA inspections on a risk-based schedule and specific adverse event reporting requirements, while 503A pharmacies are not subject to CGMP and work to “less robust production standards that provide less assurance of quality.”

What changed when the shortage ended

When a shortage ends, the copy exemption ends with it. The FDA gave compounders a short transition period instead of an immediate cut-off. The FDA’s compounder policy page lists the dates:

The tirzepatide shortage followed a similar path. The FDA decided on December 19, 2024 that it was resolved, and its grace periods have also ended.

What compounding is still allowed

The end of the shortage did not ban compounding outright. It put compounded semaglutide back under the ordinary rules, which are much tighter.

• 503A pharmacies may still compound for an individual patient on a prescription, but may not compound essentially copies “regularly or in inordinate amounts.” The FDA says it does not intend to act against a compounder that fills four or fewer prescriptions of such a product in a calendar month.
• A documented clinical difference takes a product out of the “copy” category. The FDA treats a compounded drug as a copy if it has the same active ingredient in the same, similar or easily substitutable strength and the approved product can be given by the same route, unless the prescriber determines and documents a significant difference for a named patient.
• 503B outsourcing facilities generally may not compound from bulk semaglutide at all now that it is off the shortage list and not on the 503B bulks list. In an April 30, 2026 announcement the FDA proposed formally excluding it, saying it “did not identify a clinical need.”

In practice, a service still advertising compounded semaglutide to the general public at volume, with the same strengths as the brand pens, is hard to square with these rules. Adding a vitamin or changing the flavour does not by itself make a product clinically different; the test is a documented patient-specific need.

How compounded and brand semaglutide differ

The active molecule may be the same or it may not. Beyond that, the products differ in how they are made, checked and supplied.

The salt-form problem

The FDA’s page on unapproved GLP-1 drugs says it has received reports of compounders using semaglutide sodium and semaglutide acetate. The agency says these are “different active ingredients than are used in the approved drugs” and that it is not aware of any lawful basis for compounding with them. A salt form has not been shown to behave the same way in the body as the approved ingredient.

The vial problem

A prefilled pen limits how much you can inject at once. A multi-dose vial does not. The FDA has received reports of people drawing up five to 20 times the intended amount from compounded vials, some of whom were hospitalized. The mechanics of those errors are covered in our guide to compounded GLP-1 dosing errors.

What the adverse event data shows

As of May 31, 2026, the FDA had received 990 reports of adverse events associated with compounded semaglutide and more than 730 associated with compounded tirzepatide, according to its unapproved GLP-1 page. The agency notes these figures are likely an undercount, because 503A pharmacies are not required to report adverse events.

Report counts cannot tell you how often harm happens, because nobody knows how many compounded doses were used. They do show that problems were reported often enough for the FDA to track them separately from the approved products. The side effects themselves are the same family described in our GLP-1 side effects guide.

Products sold outside any pharmacy

Compounded semaglutide from a licensed pharmacy is at least made by a regulated business for a named patient. Vials sold online without a prescription are a different category. In a 2024 study in the Journal of Medical Internet Research, researchers made test purchases from six illegal online pharmacies. Three vials arrived and three pen orders were never delivered. All three vials were judged probably substandard or falsified: endotoxin was detected in every sample, measured purity was 7.7% to 14.37% against a labeled 99%, and the semaglutide content exceeded the labeled amount by 28.56% to 38.69%.

Some sellers label these vials “for research use only.” That label does not make them a lawful source of medicine; our explainer on research use only peptides covers why. Counterfeit brand pens are a separate risk again, and the FDA has seized fakes inside the legitimate supply chain, most recently announced in December 2025. See how to spot counterfeit Ozempic.

Questions to ask if you are offered compounded semaglutide

• Who is compounding it? Ask for the name and state license of the pharmacy, or whether it is an FDA-registered 503B outsourcing facility. The FDA’s BeSafeRx page explains how to check that an online pharmacy is state-licensed.
• Why is it compounded rather than the approved product? After the shortage, a lawful copy usually needs a documented patient-specific reason.
• Which ingredient is it? Ask whether it is semaglutide base or a sodium or acetate salt.
• What is the concentration, and what will you measure with? Concentrations vary between compounders, which is one source of dosing errors.
• Is a prescription required? If not, the product is not coming from a lawful pharmacy.

If you have had a reaction to a compounded GLP-1, you or your clinician can report it through FDA MedWatch. Reports from 503A products are one of the few ways the FDA learns about them, since those pharmacies are not obliged to send them in. For the wider picture of what is and is not lawful, see are peptides legal.

Sources

• FDA: Resolution of Shortages of Semaglutide Injection Products (declaratory order, February 21, 2025)
• FDA: FDA clarifies policies for compounders as national GLP-1 supply begins to stabilize
• FDA: FDA Proposes to Exclude Semaglutide, Tirzepatide, and Liraglutide on 503B Bulks List (April 30, 2026)
• FDA: FDA’s Concerns with Unapproved GLP-1 Drugs Used for Weight Loss
• FDA: FDA warns consumers not to use counterfeit Ozempic (semaglutide) found in U.S. drug supply chain
• Ashraf AR et al. Multifactor Quality and Safety Analysis of Semaglutide Products Sold by Online Sellers Without a Prescription. J Med Internet Res, 2024
• FDA: BeSafeRx: Your Source for Online Pharmacy Information
• FDA: MedWatch Safety Information and Adverse Event Reporting Program