What Happened to Compounded Semaglutide?

It was allowed because the approved product was in short supply, and it was squeezed out once that shortage officially ended. In the United States, injectable semaglutide went onto the FDA's drug shortage list in 2022. While it was listed, federal law let compounding pharmacies and outsourcing facilities make their own versions. On 21 February 2025 the FDA declared the shortage resolved, gave compounders a short grace period to stop, and then spent the following year warning about, and acting against, what was left of the market 12. Australia had already closed pharmacist compounding of this class in October 2024 6, and the UK's regulators have concentrated on how these medicines are promoted 7.

This page is about the history and the rules: why compounding was permitted, what changed, and how regulators responded. It is not about the difference between a prescription medicine and material sold for laboratory research, which is a separate question with its own answer.

Why was semaglutide being compounded at all?

Because demand outran supply, and US law makes a specific exception for drugs in shortage. The FDA added Wegovy to its drug shortage list on 31 March 2022 and Ozempic on 23 August 2022 1. Demand for both had grown faster than the manufacturer could make them.

Normally a compounder cannot simply make a copy of an approved, commercially available medicine; that would let anyone bypass the approval process by calling their product a compounded one. A shortage changes that. When a drug is on the FDA's shortage list, compounders are permitted to make versions of it to fill the gap, and outsourcing facilities may make it from bulk ingredients 2. The exception exists so that patients are not left without treatment while supply recovers. For semaglutide, it opened the door to a very large compounded market.

What is compounding, and what do 503A and 503B mean?

Compounding is the preparation of a medicine by a pharmacist or a licensed facility, rather than its manufacture as an approved product, and 503A and 503B are the two sections of US federal law that govern it. The numbers refer to sections of the Federal Food, Drug, and Cosmetic Act.

• Section 503A covers traditional compounding pharmacies, licensed by the states, which prepare medicines for individual patients on a prescription.
• Section 503B covers outsourcing facilities, which register with the FDA, can make larger batches without individual prescriptions, and are held to manufacturing-quality requirements closer to those of drug makers.
• Neither kind of product is FDA-approved, whichever section it is made under.

That last point is the one most often lost. The FDA does not review compounded drugs for safety, effectiveness or quality before they are marketed 3. Compounding is a lawful activity with its own rules, but those rules are about who may prepare a medicine and in what circumstances, not a substitute for the approval process that the original product went through.

The distinction matters for what happened next. Outsourcing facilities generally cannot compound from bulk drug substances unless the substance is on a specific FDA list — the 503B bulks list — or the drug is in shortage 2. Once semaglutide left the shortage list, the only remaining route for them was that bulks list, which is why the FDA's later action targeted it.

When did the shortage end?

On 21 February 2025, when the FDA issued a formal order declaring the semaglutide injection shortage resolved 1. The agency said it had confirmed with the manufacturer that its product availability and manufacturing capacity could meet present and projected national demand 2.

The same thing had happened to tirzepatide a few weeks earlier. The FDA determined that the tirzepatide shortage was resolved on 19 December 2024 2. The two decisions together removed the legal basis for mass compounding of both of the leading drugs in the class.

What happened after the shortage ended?

Compounders were given a short grace period to wind down, after which the ordinary rules applied again. For semaglutide, the FDA said it would not take action against 503A pharmacies until 22 April 2025, or against 503B outsourcing facilities until 22 May 2025; both periods have ended 2. For tirzepatide the equivalent dates were 18 February and 19 March 2025 2.

After that, the "essentially a copy" rule returned. The FDA treats a compounded product as essentially a copy of an approved one when it has the same active ingredient, in the same, similar or an easily substitutable strength, by the same route — unless the prescriber documents a significant difference the patient needs 2. Pharmacies may not make copies of that kind regularly or in large numbers; the agency has said it will not act where a compounder makes four or fewer such prescriptions in a month 2. In practice, the large-scale market that the shortage had allowed lost its legal footing.

Is any compounding of semaglutide still permitted in the United States?

Only in narrow circumstances, and not on the scale the shortage allowed. For a 503A pharmacy, the question is whether a preparation counts as essentially a copy of the approved product. If a prescriber documents that an individual patient needs a significant difference from the approved drug, it is not treated as a copy; otherwise the pharmacy is limited to the small number of copies the FDA has said it will not act on 2. For a 503B outsourcing facility, the question is the bulk ingredient: it cannot compound from bulk semaglutide unless the substance is on the 503B bulks list or the drug is back on the shortage list, and semaglutide is on neither 2.

The effect is that compounding has returned to what the law intends it to be: a way of meeting an individual patient's specific need, not a parallel supply of an approved medicine. If the approved product went back into shortage, the shortage rules would apply again. That is the whole mechanism, and it explains both the rise and the fall of the market.

Why did the FDA keep warning about compounded versions?

Because of reports of harm, dosing mistakes and ingredients that were not what the approved drug contains. The FDA has repeatedly pointed out that compounded drugs are not approved and are not reviewed before marketing for safety, effectiveness or quality 3.

It has highlighted three specific concerns. First, it has received hundreds of adverse event reports involving compounded semaglutide and tirzepatide, and has singled out dosing errors with compounded injectable semaglutide 3. Second, it has warned that some products used salt forms — semaglutide sodium and semaglutide acetate — which it describes as different active ingredients from those in the approved drugs 3. Third, it has warned separately about counterfeit products claiming to be the authentic medicine, which may contain the wrong ingredient, too little, too much or none at all 3.

The salt-form point is easy to miss and important. An approved drug is approved as a specific substance. A different salt of the same molecule is, for regulatory purposes, a different active ingredient, and nothing in the approved drug's testing applies to it automatically.

What enforcement followed in the United States?

Two strands: action against marketing, and action against the bulk ingredient route. On marketing, the FDA launched a campaign against misleading drug advertising in September 2025, and in March 2026 it announced warning letters to 30 telehealth companies over compounded GLP-1 products 5. The main problems cited were claims implying that compounded products were the same as the approved drugs, and branding that obscured who had actually compounded the product 5. The agency said it had sent thousands of letters about misleading advertising in the preceding six months 5.

On bulk ingredients, the FDA announced on 30 April 2026 that it proposed not to include semaglutide, tirzepatide or liraglutide on the 503B bulks list, finding no clinical need for outsourcing facilities to compound them from bulk substances when approved products are available 4. The proposal was opened for public comment before a final decision 4. If adopted, it closes the route that outsourcing facilities would otherwise need in order to make these drugs outside a shortage.

What happened in Australia?

Australia acted earlier and more directly, by removing this class of drug from pharmacists' compounding exemption altogether. The Therapeutic Goods Administration amended the Therapeutic Goods Regulations so that medicines containing GLP-1 receptor agonists compounded on or after 1 October 2024 could no longer be compounded by pharmacists and supplied to patients 6.

The difference from the American approach is instructive. In the United States, compounding was allowed because of a shortage and restricted when the shortage ended. In Australia, the regulator decided the class should not be compounded by pharmacists at all, regardless of supply, and changed the regulations to say so.

What happened in the UK?

The UK's regulators have concentrated on promotion and on unlicensed products. In June 2026, the Medicines and Healthcare products Regulatory Agency, the Advertising Standards Authority and the General Pharmaceutical Council jointly warned businesses against promoting unlicensed weight-management products and newly licensed prescription-only medicines 7. They pointed out that medicines must be licensed by the MHRA before they are marketed, that prescription-only medicines may not be advertised to the public, and that practices such as advertising pipeline products or waiting lists were likely to break the rules 7.

The common thread across all three countries is the same principle applied through different machinery. Each regulator's concern is that a prescription medicine reaches people only as the approved product, after an individual clinical assessment, rather than as a look-alike marketed directly to consumers.

So what is the short answer?

Compounded semaglutide was a product of the shortage. Wegovy and Ozempic went onto the FDA shortage list in 2022, the law allowed compounded versions while they were listed, and the FDA declared the shortage over on 21 February 2025 1. Grace periods ended in April and May 2025 2. Since then, the FDA has warned about dosing errors and non-approved salt forms 3, acted against misleading marketing 5, and in April 2026 proposed closing the bulk ingredient route for outsourcing facilities 4.

Australia ended pharmacist compounding of the class in October 2024 6, and UK regulators have targeted promotion instead 7. Different mechanisms, one conclusion: outside a genuine shortage, regulators in all three countries want these medicines supplied as the approved product, not as a copy.