Compounded GLP-1s: what changed, and what's worth writing down
The legal ground under compounded semaglutide and tirzepatide moved between 2024 and now, and a lot of what's written about it online is out of date. Here's the timeline with FDA's own documents attached — and the one part of this that's actually a tracking problem.
We build a food and medication log. We are not clinicians, we have no view on what you should be taking, and nothing here is advice about your prescription — that conversation belongs to you and the person who writes it.
What we can do is lay out what happened, with FDA’s own filings attached to every date, because the compounded GLP-1 picture changed substantially between 2024 and now and a great deal of what’s written about it online describes a world that no longer exists. Then we’ll be specific about the one piece of this that is genuinely our business, which is smaller than a blog post usually wants its subject to be.
Why shortage status was the whole ballgame
Compounding pharmacies operate under two sections of the Food, Drug, and Cosmetic Act: 503A covers state-licensed pharmacies compounding for an individual patient, 503B covers larger outsourcing facilities. Neither is normally allowed to make copies of an approved drug. FDA’s phrasing is that a compounded drug “may not be identical or nearly identical to an FDA-approved drug unless the approved drug is on FDA’s drug shortage list” (FDA).
That “unless” is the door the entire cash-pay compounded GLP-1 market came through. Tirzepatide went onto the shortage list on 15 December 2022, semaglutide products earlier still, and for roughly two years the shortage was the legal basis for compounding them.
Then it closed.
The timeline
Tirzepatide
- 2 October 2024 — FDA determines the tirzepatide shortage resolved. A compounding trade body sues; a court sends the decision back to the agency to reconsider.
- 19 December 2024 — FDA issues a declaratory order that revokes and replaces the October decision and re-confirms that the shortage is resolved.
- 18 February 2025 — end of the period in which FDA said it would not act against 503A pharmacies compounding tirzepatide.
- 19 March 2025 — the same for 503B outsourcing facilities.
Semaglutide
- 21 February 2025 — FDA determines the semaglutide shortage resolved.
- 22 April 2025 — end of enforcement discretion for 503A pharmacies.
- 24 April 2025 — the district court denies the compounders’ request for a preliminary injunction.
- 22 May 2025 — end of enforcement discretion for 503B outsourcing facilities.
If you have read that the shortage ended in October 2024, that was true for about ten weeks and then formally wasn’t; the operative document is the December order. It’s a small distinction that matters if you’re reading anything written in between.
What was supposed to survive, and the pressure it’s under
After those dates, the remaining route was compounding genuinely tailored to an individual patient with a documented clinical reason — not a cheaper copy of the approved product. In practice a large share of the market moved to combination formulations, semaglutide mixed with B12 and similar, on the argument that a combination isn’t a copy.
FDA has been visibly unconvinced. Two data points, both from this year:
3 March 2026 — FDA announced 30 warning letters to telehealth companies over how they marketed compounded GLP-1s. The violations it described were claims implying sameness with FDA-approved products, and obscuring where the drug came from by advertising it under the telehealth firm’s own name or trademark, implying the firm was the compounder.
30 April 2026 — FDA proposed excluding semaglutide, tirzepatide and liraglutide from the 503B bulks list — the list of ingredients outsourcing facilities are permitted to compound from bulk — saying it “did not identify sufficient evidence” of a clinical need for them. The comment period closed on 29 June 2026.
That second one is a proposal, not a final rule. As of this post going up we have found no final determination, and we’re not going to forecast one. If you are on a compounded product, the status of that docket is a reasonable thing to ask your prescriber or pharmacy about, because they will hear about it before you do.
The part that is actually our business
Here is the piece of this we have standing to talk about, and it is a units problem.
On 26 July 2024 FDA issued an alert about dosing errors with compounded injectable semaglutide. The agency reported adverse events, “some requiring hospitalization, that may be related to overdoses due to dosing errors.” Its description of how:
The majority of the reports described patients mistakenly drawing up more than the prescribed dose from a multiple-dose vial during self-administration. In these instances, patients administered five to 20 times more than the intended dose of semaglutide.
And on why:
Unfamiliarity with withdrawing medication from a vial into a syringe and coupled with confusion between different units of measurement (e.g., milliliters, milligrams and “units”) may have contributed to dosing errors.
Read that last line again, because it is the structural difference between a brand pen and a compounded vial. A pen is dialled to a dose. A vial and a syringe hand you arithmetic — a concentration in mg/mL, a volume in mL, syringe markings in “units” — and ask you to do it correctly every week, often with no injection experience.
We are not going to tell you what to draw. FDA’s own recommendation is to talk to your provider or compounder about how to measure and administer the intended dose, and that is the right advice. What we’d add is downstream of it: whatever you and your prescriber settle on, the number worth recording is the milligrams you actually administered, with the date.
Not the vial’s concentration. Not the syringe units. The delivered mg. Those are three different numbers, and the failure mode in FDA’s alert is people conflating them.
The reason to write it down is unglamorous. At a check-in, “what are you actually taking?” has a correct answer, and on a compounded product that answer isn’t printed on a box anywhere. A dated list is the difference between answering it and estimating it out loud.
What that looks like here
Macroline’s medication list carries the brand products with their marketed strengths — Wegovy at 0.25 / 0.5 / 1.0 / 1.7 / 2.4 mg, Mounjaro and Zepbound at 2.5 through 15, and so on — because those are the doses that exist.
It also carries compounded semaglutide and compounded tirzepatide as their own entries, with a free-entry milligram field instead of a fixed list, precisely because a compounded dose may not match any marketed strength and a picker that forces it to would be recording a number you weren’t given. You log the mg you took; it keeps the dates.
That’s the whole feature. It doesn’t check your arithmetic, doesn’t suggest a schedule, and won’t tell you when to escalate — that is a prescriber’s job and we’ve written before about why we won’t take it. It keeps a record you can hand to someone who does have your chart.
If you want the rest of the picture on tracking through a GLP-1 — what the trials actually measured, why protein turns into the hard part, and what’s worth bringing to a first check-in — the first-month guide covers it, and the GLP-1 page covers what the app does.
Macroline is not medical advice and does not provide dosing or titration guidance. Every date and quotation above links to the FDA document it came from. Ozempic, Wegovy and Rybelsus are trademarks of Novo Nordisk; Mounjaro and Zepbound are trademarks of Eli Lilly.