Tirzepatide
FDA-approved dual GIP/GLP-1 receptor agonist with superior weight loss efficacy vs semaglutide in head-to-head data.
Tirzepatide (Tirzepatide (Mounjaro / Zepbound)). FDA-approved dual GIP/GLP-1 receptor agonist with superior weight loss efficacy vs semaglutide in head-to-head data. Typical community dosing: 2.5 → 15 mg weekly (titrated over 20+ weeks). Regulatory status: FDA-approved as Mounjaro (T2D) and Zepbound (chronic weight management).
39 residues· First described 2018
Dual GIP/GLP-1 receptor agonist; Aib at positions 2 and 13; C20 fatty diacid acylation
Overview
Tirzepatide is the first commercially available dual agonist of both the GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 receptors, developed by Eli Lilly and approved as Mounjaro for type 2 diabetes and Zepbound for chronic weight management. The addition of GIP activity is what differentiates tirzepatide from single-agonist GLP-1s like semaglutide - and is thought to explain its superior efficacy, with the SURMOUNT-1 trial showing ~22.5% mean body weight reduction at 72 weeks at the maintenance dose.
Head-to-head, tirzepatide has outperformed semaglutide on weight, HbA1c, and lipid endpoints. The cardiovascular outcomes data is still maturing, but metabolic biomarkers move in the same favorable directions - often with steeper magnitude. Most users who have tried both report a different subjective experience: tirzepatide tends to feel "cleaner" in terms of appetite reduction, with somewhat less overt nausea profile for many.
Because the titration runs longer (up to 6 steps vs 5), and doses go higher (up to 15 mg vs 2.4 mg), the protocol decisions around tirzepatide are more nuanced. Tracking the right biomarkers on a cadence that captures the curve - not just endpoints - is where the value of a structured tracking tool really shows.
Mechanism of Action
Tirzepatide binds and activates both the GIP and GLP-1 receptors. GLP-1 activity produces glucose-dependent insulin release, glucagon suppression, delayed gastric emptying, and appetite reduction. GIP activity adds additional insulinotropic effect and has been shown to modulate adipose tissue function, potentially improving the quality of weight loss (higher fat-to-lean ratio). The synergy between the two pathways is thought to be non-additive - more than the sum of its parts.
Community Usage Patterns
Standard titration per label: 2.5 mg weekly × 4 weeks, increasing in 2.5 mg steps every 4 weeks to 10–15 mg maintenance. Many users hold at 5 mg or 7.5 mg for extended periods if response is adequate. Compounded versions are common through 503A pharmacies. Critical tracking: HbA1c at baseline + 3 months + 6 months, lipid panel (with ApoB) quarterly, weight weekly, and any GI side effects logged against dose changes.
Education only - not medical advice. Any protocol change should involve your licensed provider.
Biomarkers to Track
When running Tirzepatide, these are the biomarkers most commonly tracked to assess response and safety:
Blood Work Checklist
Before starting Tirzepatide, baseline the right panel. The Peptide Blood Work Checklist covers the full baseline panel, what to add for Tirzepatide's class, and when to retest.
See the peptide blood work checklist →Reconstitution Calculator
Free calculator for Tirzepatide reconstitution math - vial size, BAC water volume, and exact syringe units.
Open Tirzepatide calculator →Side Effects & Monitoring
What Tirzepatide side effects are commonly reported, when they appear, the red flags worth a provider call, and the biomarkers that catch issues early.
Tirzepatide side effects & what to track →Results & What to Track
What Tirzepatide results actually look like in the data - the markers to measure, when they tend to move, and how to tell a real result from placebo.
Tirzepatide results & how to measure them →Related Reading
Related Peptides
Tirzepatide Head-to-Head Comparisons
Conditions Tirzepatide is Commonly Researched For
Frequently Asked Questions
What is Tirzepatide?
Tirzepatide is the first commercially available dual agonist of both the GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 receptors, developed by Eli Lilly and approved as Mounjaro for type 2 diabetes and Zepbound for chronic weight management. The addition of GIP activity is what differentiates tirzepatide from single-agonist GLP-1s like semaglutide - and is thought to explain its superior efficacy, with the SURMOUNT-1 trial showing ~22.5% mean body weight reduction at 72 weeks at the maintenance dose.
How does Tirzepatide work?
Tirzepatide binds and activates both the GIP and GLP-1 receptors. GLP-1 activity produces glucose-dependent insulin release, glucagon suppression, delayed gastric emptying, and appetite reduction. GIP activity adds additional insulinotropic effect and has been shown to modulate adipose tissue function, potentially improving the quality of weight loss (higher fat-to-lean ratio). The synergy between the two pathways is thought to be non-additive - more than the sum of its parts.
What is the typical dosing for Tirzepatide?
2.5 → 15 mg weekly (titrated over 20+ weeks)
What biomarkers should I track on Tirzepatide?
Common biomarkers tracked on Tirzepatide protocols: HbA1c, Fasting glucose, ApoB, Triglycerides, LFTs, Weight.
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Start tracking →This page is informational and does not constitute medical advice. MyProtocolStack is a tracking and education platform. Work with a licensed provider before starting, changing, or stopping any protocol.