For most of 2023 and 2024, compounded semaglutide and tirzepatide filled a regulatory gap. Because Novo Nordisk's and Eli Lilly's branded products sat on the FDA Drug Shortage List, state-licensed pharmacies (503A) and outsourcing facilities (503B) could legally prepare copies under Section 503A and 503B of the Food, Drug, and Cosmetic Act. Millions of patients received compounded GLP-1s through telehealth clinics at a fraction of the branded price.
That window closed in stages through 2025. The FDA removed tirzepatide from the shortage list on December 19, 2024, and semaglutide on February 21, 2025. Enforcement discretion for 503A pharmacies ended on February 18 and April 22, 2025, respectively, with parallel 503B deadlines a month later. In September 2025, the agency issued more than 50 warning letters to compounders and online marketers in a coordinated action — the largest single enforcement sweep against the compounded-GLP-1 industry to date.
The piece below walks through what the warning letters actually named, where the 503A pathway still permits patient-specific compounding in 2026, and what this means for readers evaluating compounded GLP-1 access.
The shortage-list status that made compounding legal
Under Section 503A, a state-licensed pharmacy may compound a drug that appears on the FDA Drug Shortage List without violating the prohibition against making copies of commercially available FDA-approved drugs. Outsourcing facilities registered under Section 503B operate under a parallel exception. Both exceptions disappear the moment the reference product comes off the shortage list.
The FDA resolved the tirzepatide shortage in a December 19, 2024 declaratory order and the semaglutide shortage on February 21, 2025, citing stabilized manufacturer supply. Those two dates, not the September 2025 warning letters, are the load-bearing regulatory events. Everything afterward is enforcement of a rule that already changed.
The agency granted transition windows: 503A compounders had until February 18, 2025 (tirzepatide) and April 22, 2025 (semaglutide) to stop production; 503B outsourcing facilities had one additional month each. A lawsuit filed February 24, 2025 by the Outsourcing Facilities Association seeking a preliminary injunction against the semaglutide delisting was denied on April 24, 2025.
What 503A still permits in 2026
The current environment is frequently mischaracterized as a total ban. It is not. A state-licensed 503A pharmacy may still compound semaglutide or tirzepatide when three conditions are met: (1) a valid patient-specific prescription written after a documented prescriber evaluation, (2) a clinical justification that the commercially available FDA-approved product is not appropriate for that patient, and (3) compliance with state pharmacy law and USP compounding standards.
What is no longer permitted under 503A is bulk compounding for office stock, speculative production anticipating demand, or marketing compounded versions as generic equivalents. Neither semaglutide nor tirzepatide appears on the FDA 503B bulks list, which means 503B outsourcing facilities cannot compound these active ingredients from bulk drug substance at all going forward.
Inside the September 2025 warning-letter cohort
The September 2025 FDA action targeted a mix of compounding pharmacies, telehealth marketers, and online retailers. The agency's stated concerns clustered around three categories.
First, false-equivalence marketing. The FDA flagged claims that compounded products were "generic versions" or contained the "same active ingredient" as FDA-approved Ozempic, Wegovy, Mounjaro, or Zepbound as false or misleading, because compounded drugs are not reviewed for safety, efficacy, or quality.
Second, sterility and potency failures. A September 9, 2025 warning letter to DirectMeds documented sterility-specification failures and potency-specification failures in sterile GLP-1 injectables distributed between July 2024 and May 2025 — a window that overlapped with peak compounded-GLP-1 volume.
Third, adverse event signal. As of April 30, 2025, FDA had received 520 adverse event reports tied to compounded semaglutide and 480 tied to compounded tirzepatide. The agency has not published a causal analysis but cited the AE volume as justification for escalated enforcement.
Reader implications
For patients currently prescribed compounded semaglutide or tirzepatide through a telehealth platform, the practical questions in 2026 are whether the prescribing pharmacy is 503A-licensed in the patient's state, whether a genuine prescriber relationship exists, and whether the compounded preparation is patient-specific. Bulk-office-stock compounding for these two actives is no longer permitted under either pathway.
Patients seeking branded product face two separate questions — insurance coverage and cash price — that sit outside the compounding framework entirely. PeptaHub's GLP-1 pillar covers the therapeutic and dosing evidence; our legal-status guide walks through the statutory pathways in more depth, and our general peptide-safety reference covers the sourcing risk profile.
The compounding market for these two GLP-1s has contracted sharply since February 2025. Whether the remaining 503A pathway stays viable at scale, or whether further FDA rulemaking narrows it further, is the regulatory question to watch through 2026.