Tirzepatide is a dual GLP-1 and GIP receptor agonist developed by Eli Lilly and FDA-approved as Mounjaro (type 2 diabetes) and Zepbound (obesity). The dual mechanism produces greater weight-loss outcomes than GLP-1-only drugs in head-to-head trials. Research-grade tirzepatide sold by peptide vendors is the same molecule but is not pharmaceutical-grade.
Research notes
How does Tirzepatide work?
Tirzepatide hits two incretin receptors: GLP-1 and GIP. The dual agonism produces a larger weight-loss and glycemic effect than GLP-1 monotherapy at comparable doses. Marketed as Mounjaro for type 2 diabetes and Zepbound for obesity by Eli Lilly.
What doses are used in research?
Standard escalation schedule starts at 2.5 mg weekly, increasing every four weeks through 5, 7.5, 10, 12.5, and 15 mg. The Surmount trials used this schedule with optimal weight-loss outcomes at the 10–15 mg range.
Which vendors carry Tirzepatide?
Tirzepatide is the most-stocked compound across the audited vendor pool — every major research vendor lists it, which makes it the natural starting point for cross-vendor purity comparisons. Cross-lab agreement on tirzepatide tends to be tight (<1 percentage point) at the top vendors and looser (2–4 points) at the bottom of the pack.
What it's researched for
- weight loss
- type 2 diabetes
Where to source it
ALL 10 VENDORS →RANKED BY COMPOSITE SCORE · PRICES ARE SNAPSHOTS FROM THE PRICE INDEX · PER-MG IS A WITHIN-COMPOUND COMPARATOR
Frequently asked about Tirzepatide
What is tirzepatide?
Tirzepatide is a synthetic peptide that activates two hormone receptors simultaneously: GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide). It was developed by Eli Lilly and is the first approved dual incretin agonist.
How is tirzepatide different from semaglutide?
Semaglutide acts only at the GLP-1 receptor. Tirzepatide adds GIP-receptor activation, which in head-to-head trials (SURPASS, SURMOUNT) has produced greater weight-loss and HbA1c-reduction outcomes than semaglutide at comparable doses. The trade-off is a slightly different gastrointestinal side-effect profile.
What's the difference between Mounjaro and Zepbound?
Both are tirzepatide. Mounjaro is FDA-approved for type 2 diabetes. Zepbound is FDA-approved for obesity. The molecule, dosing schedule, and titration ladder are the same; the labeling differs by approved indication.
What doses are used in tirzepatide research?
Published research most often references the FDA-approved titration ladder: 2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg weekly subcutaneous. The half-life is approximately 5 days. Doses cited here are research-protocol references, not human-use recommendations.
What is the typical purity of research-grade tirzepatide?
Janoshik Analytical tests in our corpus typically show 96–99% purity by HPLC for tirzepatide from audited vendors. The molecule's mass-spectrometry identity is well-characterized. Per-vendor purity and any flagged lots are in the leaderboard on this page.