Almost everything written about compounded GLP-1 medicines rests on one sentence: compounding was allowed because the drugs were in shortage, and it stopped when the shortage ended.
That sentence describes one of the two federal compounding statutes and not the other. The word "shortage" does not appear anywhere in the section that governs ordinary pharmacies.
Two statutes, two tests
Compounding in the United States runs on two sections of the Federal Food, Drug, and Cosmetic Act, codified at 21 U.S.C. 353a and 353b. They exempt compounded preparations from the approval requirements that apply to manufactured drugs, on different conditions.
| Section 503A (21 U.S.C. 353a) | Section 503B (21 U.S.C. 353b) | |
|---|---|---|
| Who | licensed pharmacists and physicians | registered outsourcing facilities |
| The copy rule | must not compound "regularly or in inordinate amounts … any drug products that are essentially copies of a commercially available drug product" | the drug "is not essentially a copy of one or more approved drugs" |
| The escape hatch | a change "made for an identified individual patient, which produces for that patient a significant difference, as determined by the prescribing practitioner" | the drug "appears on the drug shortage list in effect under section 356e" |
| Mentions of "shortage" in the section | 0 | yes, repeatedly |
Both columns were read from the US Code on 2026-09-20. The count in the last row is a full-text search of 21 U.S.C. 353a: the word "shortage" occurs zero times, and the shortage-list section, 356e, is never cited.
Where the shortage list actually appears
It appears twice in section 503B, and both are load-bearing.
In the definition of what an outsourcing facility may not copy, at 353b(d)(2)(A): a drug identical or nearly identical to an approved drug, "unless, in the case of an approved drug, the drug appears on the drug shortage list in effect under section 356e of this title."
And in the conditions on bulk drug substances, at 353b(a)(2)(ii): permitted where "the drug compounded from such bulk drug substance appears on the drug shortage list in effect under section 356e of this title at the time of compounding, distribution, and dispensing."
That last clause is stricter than it reads. The drug has to be on the list at three separate moments, not at the moment the facility decided to start.
What section 503A says instead
A traditional pharmacy's exemption turns on a clinical judgement about one patient:
the term "essentially a copy of a commercially available drug product" does not include a drug product in which there is a change, made for an identified individual patient, which produces for that patient a significant difference, as determined by the prescribing practitioner, between the compounded drug and the comparable commercially available drug product
Three limits are written into that sentence and all three are routinely dropped when it is paraphrased. The change must be for an identified individual patient, not for a product line. It must produce a significant difference for that patient. And the person who determines it is the prescribing practitioner, not the compounder and not the seller.
This is also why so many compounded GLP-1 preparations are offered with something added, or at a strength or concentration the branded pens do not use. Whether any specific formulation meets the statutory test is a legal question about that formulation and those prescriptions, and nothing on this page answers it for any seller.
The shortage list, as it stands today
Because the 503B route depends entirely on the list, the list is checkable. These are the results of searching FDA's shortage database by molecule on 2026-09-20.
| Molecule | Records | Status |
|---|---|---|
| tirzepatide | 0 | no records of any kind |
| semaglutide | 3 | no shortage entry; the only records are "To Be Discontinued" for semaglutide tablets, posted 2026-06-04 |
| dulaglutide | 0 | no records |
| exenatide | 0 | no records |
| liraglutide | 11 | "Current" shortage entries for liraglutide injection, reason "Delay in shipping of the drug", last updated 2026-08-25 — and a "To Be Discontinued" entry posted the same day |
The only GLP-1 molecule on the shortage list is liraglutide.
It is the oldest molecule in the class and the weakest in its own label: SAXENDA reports a 7.4% weight reduction at week 56 against 20.9% for tirzepatide at week 72 on the posted-results page. It is on the list because of a shipping delay. And it is being discontinued, on a notice posted the same day as its most recent shortage update.
So the section 503B shortage route stands open for the product almost nobody is asking for, and shut for the two the entire compounded market was built on.
What follows, and what does not
Three things follow from the text.
"The shortage ended" and "compounding ended" are not the same sentence. They are the same sentence for outsourcing facilities and they are not a sentence about pharmacies at all.
The 503A route was never about supply. Its test is clinical and individual, and it was available before the shortage and remains available after it — on its own terms, which are narrow and patient-specific.
The 503B prohibition is flat; the 503A one is a quantity rule. A pharmacy is barred from compounding copies "regularly or in inordinate amounts," a threshold the statute delegates to the Secretary rather than fixing itself.
What does not follow is any conclusion about a particular product or seller. This page reports what two sections of the US Code say and what a federal database returned on one dated reading. It does not assess whether any compounded preparation on sale is lawful, safe, or what its label claims — and a statutory route being open is not evidence that any given product travelling down it is any of those things.
The molecule-level picture for semaglutide, including the tentatively approved generic and the tablet discontinuation, is on the compounded semaglutide page. What compounded vials change about dose arithmetic is a separate problem, and a documented source of real-world error. Prices are on the cost page.
Sources
- 21 U.S.C. 353a (FD&C Act section 503A), full text, read 2026-09-20.
- 21 U.S.C. 353b (FD&C Act section 503B), full text, read 2026-09-20.
- FDA drug shortage database via the openFDA
drug/shortagesendpoint, queried by generic name for semaglutide, tirzepatide, liraglutide, dulaglutide and exenatide, read 2026-09-20. - SAXENDA label (liraglutide), DailyMed SPL, version dated 2026-06-15, read 2026-09-20.