Compounded semaglutide and tirzepatide: where things stand

Why compounded versions existed

Compounded drugs are mixed by a pharmacy rather than made by a drug company under an FDA approval. FDA's position is that a compounded drug "might be appropriate if a patient's medical need cannot be met by an FDA-approved drug, or the FDA-approved drug is not commercially available." Compounded drugs are not FDA-approved, which means the agency "does not review compounded drugs for safety, effectiveness or quality before they are marketed."⁴

Federal law also lets pharmacies make copies of a drug while it is on FDA's drug shortage list. That is what happened with GLP-1 drugs. Demand outran supply: Wegovy went on the shortage list on March 31, 2022, Ozempic on August 23, 2022, and tirzepatide (Mounjaro and Zepbound) on December 15, 2022.^1,2 For roughly two to three years, compounded semaglutide and tirzepatide filled the gap, usually in multi-dose vials rather than the pre-filled pens the approved products come in.

The shortages are over

FDA declared the tirzepatide shortage resolved on October 2, 2024. A lawsuit sent that decision back to the agency, and FDA reached the same conclusion again on December 19, 2024.^2,3 It declared the semaglutide shortage resolved on February 21, 2025.¹ FDA noted that people "may still see intermittent and limited localized supply disruptions" as stock moves from manufacturers to local pharmacies.³

What it means for pharmacies: 503A and 503B

Two kinds of compounders work under different sections of federal law. Which one made a product decides what it may do now that the shortages are over.

Adding a vitamin doesn't make a copy into something else. FDA gives the example of semaglutide combined with vitamin B12: it may still count as essentially a copy if it is used the same way and the amounts are within 10% of the strengths of the approved products.³ FDA also says the safety and effectiveness of combining semaglutide with other ingredients, such as B12, B6, L-carnitine or NAD, "has not been established."⁸

For outsourcing facilities, the open question is the 503B bulks list. On April 30, 2026, FDA proposed leaving semaglutide, tirzepatide and liraglutide off it, saying it found "no clinical need" for outsourcing facilities to compound them from bulk substances.⁵ The Federal Register notice says FDA does not treat shortages or backorders as "clinical need."⁶ The comment period was extended to July 30, 2026.⁷ As of November 1, 2026, the Federal Register shows no final decision.

Dosing errors: units, milliliters and milligrams

The approved injectable semaglutide products are dosed in milligrams, come in standard concentrations and were, when FDA wrote its alert in July 2024, sold only in pre-filled pens. Compounded versions usually come in multi-dose vials. Their instructions may give the dose in "units," whose volume depends on the concentration, and some patients were sent syringes much larger than the volume they needed.⁸

FDA's alert says most reports involved patients "mistakenly drawing up more than the prescribed dose from a multiple-dose vial," which led to five to 20 times the intended dose. In other reports, the error was the prescriber's: converting milligrams to units or milliliters wrongly led to five to 10 times the intended dose. Reported effects included nausea, vomiting, abdominal pain, fainting, headache, dehydration, acute pancreatitis and gallstones, and some patients were hospitalized. Because semaglutide's half-life is about a week, FDA notes that watching and treating an overdose can take a long time.⁸

Poison-center data show the same pattern. A review of California Poison Control System records from December 2017 to December 2023 found 36 exposures involving compounded GLP-1 drugs. In 33 of them (91.7%), an administration error was the main reason for the call.¹³ An earlier case series described two patients who injected ten times their intended dose from compounded vials.¹⁴ FDA has also received reports from people prescribed compounded semaglutide or tirzepatide at doses beyond the approved labels, or raised faster than the labels' schedules.⁴

The salt-form problem

Ozempic, Wegovy and the other approved semaglutide products contain semaglutide in its base form. FDA says some compounders have used salt forms instead, such as semaglutide sodium and semaglutide acetate. These "are different active ingredients than are used in the approved drugs." FDA says it does not know whether they have the same chemical and pharmacologic properties, and that it is "not aware of any lawful basis for their use in compounding."^4,8

Where the powder comes from matters too. In September 2025, FDA created a "green list" import alert for GLP-1 active ingredients. Bulk powder from facilities FDA hasn't inspected or evaluated can now be held at the border. Of the 48 GLP-1 ingredient sites FDA evaluated, 21% were found noncompliant. FDA also notes that 503A pharmacies are exempt from manufacturing quality rules, including the requirement to check an ingredient's purity and potency against specifications. That raises the risk that a bad batch of powder goes uncaught.^10,18

Marketing claims and "research use only" vials

In February 2026, FDA said companies may not claim that compounded products are generic versions of, or the same as, FDA-approved drugs. They also may not say the products use the same active ingredient or are clinically proven to work.¹¹ In March 2026, FDA announced 30 warning letters to telehealth companies, mostly over claims implying sameness with approved products and labels that hid which pharmacy actually made the drug.¹²

Vials sold online as "for research purposes" or "not for human consumption" are a separate problem. FDA has warned sellers of semaglutide, tirzepatide, retatrutide and other GLP-1 drugs labeled that way but sold to consumers with dosing instructions. It calls them "of unknown quality." FDA also says retatrutide and cagrilintide cannot be used in compounding at all, because they are not components of any approved drug.⁴

The list above is condensed from FDA's consumer page.⁴ FDA also reports compounded GLP-1 products that arrived warm or with too little ice.

The approved options have changed

The approved options have also changed since the shortages began. FDA approved Wegovy tablets, an oral semaglutide for weight management, on December 22, 2025.¹⁵ It approved a higher-dose Wegovy injection (7.2 mg, Wegovy HD) on March 19, 2026.¹⁶ On April 1, 2026, it approved Foundayo (orforglipron), a daily pill that acts on the GLP-1 receptor but is not a peptide.¹⁷ Zepbound gained an indication for moderate to severe obstructive sleep apnea in adults with obesity in December 2024.¹⁹ Whether any of these suits a particular person is a question for a prescriber, but their existence is part of why FDA treats the approved drugs as commercially available.

What isn't settled

• The 503B bulks list. FDA's decision on keeping semaglutide, tirzepatide and liraglutide off it is still a proposal as of November 1, 2026.^6,7
• Restricting the ingredients themselves. FDA said in February 2026 that it intends to restrict GLP-1 active ingredients meant for mass-marketed compounded drugs.¹¹ We found no rule or notice on FDA's site or in the Federal Register putting that into effect yet.
• How often things go wrong. Adverse-event reports can't show cause, and 503A pharmacies aren't required to report them to FDA, so the counts are likely low.⁴ FDA's dosing-error alert gives no count of cases at all.⁸
• Product quality across the market. There is no FDA-reviewed data on how consistent compounded GLP-1 products are in strength, purity or sterility. That is the gap approval is meant to fill.
• Liraglutide. It is still on the shortage list, which keeps the shortage route open for it in principle, while FDA's bulks-list proposal would close the other route.^6,9

We'll update this guide when FDA finalizes the bulks-list decision or the shortage list changes, and the "Last reviewed" date at the top will say when we last checked.