What Is Tirzepatide?
Tirzepatide is a dual GIP/GLP-1 receptor agonist research peptide. Here is what it is, what to look for on a COA, and where to find verified vendors.
Tirzepatide is a synthetic peptide developed as a dual agonist of the glucose-dependent insulinotropic polypeptide (GIP) receptor and the glucagon-like peptide-1 (GLP-1) receptor. It is approved by the FDA under the brand names Mounjaro and Zepbound. Research-grade tirzepatide is also sold by US peptide vendors for laboratory use.
Structure and spec
Tirzepatide has a molecular weight of approximately 4813 grams per mole. Like other GLP-1 family peptides, vendors commonly sell it under code names (GLP-2T, GLP2-T, TZ) due to FDA enforcement against unauthorized marketing.
FDA enforcement context
Tirzepatide is among the GLP-1 compounds with the most active FDA enforcement against unauthorized marketing for human use. Multiple US vendors have received FDA warning letters specifically for marketing Tirzepatide for human consumption. The FDA looks at the molecule shipped, not the label name.
What to look for in a Tirzepatide COA
Verify the molecular weight matches 4813 g/mol on the COA, confirm purity above 99 percent, ensure the testing lab is named, and look for endotoxin testing, which HPLC purity cannot detect. Multi-batch testing patterns are stronger than single-batch reports.
Where to buy Tirzepatide
See our independent ranking of US vendors carrying verified Tirzepatide:
Frequently Asked Questions
Is research-grade Tirzepatide the same as Mounjaro?
Research-grade Tirzepatide is the same molecule as the FDA-approved drug Mounjaro/Zepbound, but it is not manufactured under FDA-regulated pharmaceutical conditions. Quality varies dramatically by vendor.
Why do vendors use code names for Tirzepatide?
Most US vendors sell Tirzepatide under code names like GLP-2T, TZ, or TIR due to ongoing FDA enforcement against marketing it for human use. The chemical identity is unchanged; only the label is obfuscated.
How is Tirzepatide tested?
Premium vendors use HPLC for purity, Mass Spectrometry for identity confirmation, USP 85 for endotoxin, and ideally USP 71 for sterility. Identity is critical for Tirzepatide given the FDA-obfuscation labeling environment.