Tirzepatide: what is legal, and what is being sold

By Brian Williams, Co-founder & Research EditorFact-checked by Megan WilliamsUpdated August 29, 2026

The short answer

Tirzepatide is FDA-approved in the United States, so the drug itself is legal to prescribe. It is also not on the 503A Bulks List, which is what governs whether a pharmacy may compound its own version — and that is the question worth asking here, as of 2026-08-29. The Pharmacy Compounding Advisory Committee has never considered it, so there is no vote to report — it is investigational, and the routes to it are set out below.

What FDA actually evaluated

FDA assessed Tirzepatide for one thing: type 2 diabetes (mounjaro) and chronic weight management (zepbound), each with its own labelled population and dosing..

Use outside the labelled populations, and every use of a compounded copy, which carries no approved labelling at all.

Full regulatory status

FDA-approved drug?Yes. Eli Lilly markets FDA-approved tirzepatide products in the US — Mounjaro and Zepbound, including KwikPen and autoinjector presentations, all confirmed in Drugs@FDA.
What has been evaluatedType 2 diabetes (Mounjaro) and chronic weight management (Zepbound), each with its own labelled population and dosing.
PCAC recommendationNever considered — no nomination has reached the committee
FDA reviewers' positionNot applicable. Tirzepatide is an approved drug and has never been before the Pharmacy Compounding Advisory Committee.
Category 2 statusNot applicable. The interim 503A categories cover bulk substances nominated for compounding. Tirzepatide is an approved drug and is not on the 503A Bulks List.
503A Bulks List todayNot on the 503A Bulks List. The relevant bar is section 503A(b)(1)(D), which stops a pharmacy regularly compounding what is essentially a copy of a commercially available drug. FDA first determined the tirzepatide shortage resolved on 2 October 2024, re-evaluated and reaffirmed that on 19 December 2024, and set 18 February 2025 as the end of enforcement discretion for 503A pharmacies. Those dates have passed.
503B statusNot on the 503B Bulks List. FDA set 19 March 2025 as the end of enforcement discretion for outsourcing facilities compounding tirzepatide injection products that are essentially a copy of an approved drug. That date has passed.
Prescription statusPrescription-only, and the lawful version is the approved product. As with semaglutide, compounding is not categorically forbidden — a prescriber can document that a particular patient needs a change from the approved product that makes a significant difference for them — but the mass-market compounded tirzepatide business no longer has a legal basis.
Next federal eventNo scheduled federal event specific to tirzepatide. FDA's February 2026 announcement of intended action on GLP-1 active ingredients is the live thread; any rulemaking or import restriction would appear in the Federal Register.

If you compete in sport

No substance-specific WADA determination for tirzepatide was located. That means none was found, not that it is permitted.

We could not find a substance-specific ruling. Treat this as unknown, not as permission, and check with your governing body before use.

Why FDA's own reviewers recommended against it

What you can actually do today

Tirzepatide is sold widely as a “research chemical” and through telehealth as a compounded product. FDA named it alongside retatrutide in the 31 March 2026 warning letter to Gram Peptides, treating “research use only” products as unapproved new drugs under section 505(a), and named it again on 14 April 2026 in the letter to New Life Pharma over sterile multi-dose vials. On 1 May 2026 it wrote to a Chinese manufacturer over GLP-1 active-ingredient supply. The supply chain behind the cheap version is what those letters describe.

What would have to happen for this to change

  1. 1FDA completes its own evaluation. The advisory vote is non-binding — FDA can accept or reject it.
  2. 2FDA publishes a proposed rule in the Federal Register identifying substances proposed for inclusion or exclusion, with its reasoning.
  3. 3A public comment period opens. Anyone may submit evidence and scientific or legal objections.
  4. 4FDA reviews the comments and the administrative record.
  5. 5FDA publishes a final rule, or withdraws or modifies the proposal.
  6. 6The final rule takes effect and amends the list at 21 CFR 216.23.

Sources

See the status of all seven peptides side by side in the FDA 503A compounding tracker. Or read our full guide to Tirzepatide.

Medical Disclaimer: This content is for informational purposes only and should not be considered medical advice. Always consult with a qualified healthcare provider before beginning any peptide therapy treatment.