U.S. regulatory status

Tirzepatide (compounded)

Also known as Mounjaro, Zepbound, compounded tirzepatide

RestrictedEnforcement discretion ended; broad compounding no longer permitted. 503B exclusion proposed - comments closed Jul 30, 2026, decision pending

Is compounded tirzepatide legal right now?

Tirzepatide is an FDA-approved drug (Mounjaro, Zepbound), not a 503A bulk substance.

After the FDA declared its shortage resolved in late 2024, the temporary enforcement discretion for compounding copies ended on February 18, 2025 for 503A pharmacies and March 19, 2025 for 503B outsourcing facilities; a federal court upheld the FDA’s shortage determination in 2025. Broad compounding is no longer permitted - only narrow patient-specific 503A compounding for a documented clinical need remains - and the FDA has been issuing warning letters.

On September 18, 2026 it warned Empower Pharmacy, a Houston compounding pharmacy, that its tirzepatide/niacinamide injections appear to be essentially copies of the approved drug, and questioned “significant difference” statements repeated verbatim across many prescriptions. In April 2026 the FDA proposed to permanently exclude tirzepatide - along with semaglutide and liraglutide - from the 503B bulks list; the public comment period closed July 30, 2026 (extended from June 30) and the FDA’s final determination is pending, with no announced date.

Restricted: Prescription-only, banned, controlled, or under active FDA enforcement.

Verified Oct 9, 2026 (ET) · status held since Mar 19, 2025

Primary source: Federal Register All 8 sources Reconstitution calculator Compared: vs Mounjaro / Zepbound Compared: vs Semaglutide

Where it sits in the process

Nominated (passed)
Under review (passed)
Rulemaking (stalled here - not advancing)
Compounding-legal (not reached)

Not on a path to the 503A list right now. The process stalled or reversed at this stage - read the status above. Sitting at an earlier step is not a sign it will advance.

What changed last

Sep 18, 2026
FDA warning letter to Empower Pharmacy, a Houston compounding pharmacy: its tirzepatide/niacinamide injections appear to be essentially copies of the approved drug. No rule changed; routine compounding of copies was already restricted.
EnforcementView on fda.gov
Jul 30, 2026
Public comment period closed on the FDA’s proposal to permanently exclude tirzepatide from the 503B bulks list (extended from June 30). The proposal is not final - the FDA is now reviewing the record, with no announced decision date.
Comment deadlineView on govinfo.gov
Apr 30, 2026
FDA proposed to permanently exclude tirzepatide from the 503B bulks list, alongside semaglutide and liraglutide. This is a proposal in a comment period, not a final change.
Review scheduledView on federalregister.gov
Mar 19, 2025
503B enforcement discretion for compounding tirzepatide ended (503A ended February 18, 2025), following the resolved shortage.
EnforcementView on pharmacytimes.com

Status elsewhere

Tirzepatide (compounded): regulatory status by jurisdiction
Jurisdiction	Status	Note
United States (FDA)	Restricted	Enforcement discretion ended Feb 18, 2025 (503A, as announced; the FDA’s Sep 2026 Empower letter dates it Mar 5) / Mar 19, 2025 (503B); FDA proposed permanent 503B exclusion (Apr 2026). Narrow 503A exception remains. Sep 18, 2026: FDA warning letter to Empower Pharmacy over tirzepatide/niacinamide injections that appear to be essentially copies.
Australia (TGA)	Restricted	GLP-1 compounding prohibited since Oct 1, 2024; remains Schedule 4.
United Kingdom (MHRA)	Restricted	Licensed prescription-only medicine; no legitimate compounding pathway; MHRA enforces against unlicensed product.
European Union (EMA)	Restricted	Licensed prescription-only medicine EU-wide (Mounjaro, authorised 2022); unauthorised versions cannot be marketed, with pharmacy compounding exemptions and enforcement handled at member-state level.
Canada (Health Canada)	Restricted	Authorized prescription-only medicine (Mounjaro); compounded copies of marketed drugs are not permitted outside a shortage, and Health Canada warns selling unauthorized versions is illegal in Canada.
Sport / anti-doping (WADA)	Unscheduled	Not prohibited; added to the WADA Monitoring Program effective Jan 1, 2026. WADA confirmed GLP-1 status is unchanged for 2027 (Sep 21, 2026).

The U.S. status is watched by automation every six hours. Statuses elsewhere change less often and are covered by a monthly wide-net sweep, then re-verified whenever a lead surfaces - this entry’s last-verified date covers every row above. How we track it

Sources & transparency

Sources for this entry

Federal Register - 503B bulk drug substances clinical-need proposal (FR 2026-08552) Federal Register · primaryMay 1, 2026 proposal not to include semaglutide, tirzepatide, and liraglutide on the 503B bulks list (Docket FDA-2018-N-3240); set the original June 30, 2026 comment deadline.
FDA - warning letter, Empower Pharmacy (Sep 18, 2026) FDA · primaryTirzepatide/niacinamide injections appear to be essentially copies of FDA-approved tirzepatide; “significant difference” statements repeated verbatim across many records.
Federal Register - comment-period extension (FR 2026-12937) Government · primaryJune 26, 2026 notice extending the comment deadline on the 503B exclusion proposal to July 30, 2026.
Health Canada alert on fake/unauthorized GLP-1 drugs (Jan 21, 2026) Health Canada · primaryBasis for the Canada (Health Canada) status row.
EMA EPAR - Mounjaro (tirzepatide) EU · primaryBasis for the European Union (EMA) status row.
WADA - 2027 Prohibited List published (Sep 21, 2026) WADA · primaryThe 2027 List takes effect Jan 1, 2027.
Pharmacy Times - FDA moves to close the door on compounded GLP-1s AnalysisApril 2026 proposal; enforcement discretion ended; 503A/503B compounding no longer broadly permitted.
EMJ - GLP-1 receptor agonists on WADA Monitoring Program AnalysisTirzepatide monitored (effective Jan 1, 2026), not prohibited.

Last verified by a human: Oct 9, 2026 (ET) · how we verify
Who runs this: Peptlas Research Team - independent. About us.
What we sell: Nothing. No products, no affiliates, no sponsored placements.

This page reports publicly available regulatory status for information only. It is not medical or legal advice and makes no health claim. See our full disclaimer.