Tirzepatide
Dual GLP-1/GIP agonist — Mounjaro and Zepbound
Experimental material. Read before using anything from here.
Nothing on this page is a medical recommendation, prescription or treatment plan. It is an organized translation of protocols circulating in research communities and, where it exists, of what published trials tested. The two are marked differently — and they are not equivalent.
Most of the compounds here have no FDA approval for human use. Several are sold labeled "research use only", which means they have not gone through purity, sterility or dosage controls for human consumption. A community-reported dose is not a validated dose: it is what someone reported having done.
Talk to a licensed health professional before considering any of these compounds. If you already use one and feel anything unexpected, seek care — do not wait for the next routine test.
Absolute contraindication, in Brazil and in the United States
Tirzepatide carries an FDA black box warning for thyroid C-cell tumors in rats, dependent on dose and treatment duration, at clinically relevant exposures. Whether it causes them in humans is unknown.
It is contraindicated in anyone with a personal or family history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia type 2 (MEN 2). Unlike semaglutide, the Brazilian package insert for MOUNJARO carries this contraindication in section 4, with the same scope as the American one. It is also contraindicated in anyone who has had severe hypersensitivity: there are reports of anaphylaxis and angioedema.
This warning was not on this page until September 4, 2026, and the failure was this site's, not the source's. The audit of the dose tables against the FDA package inserts is in The GLP-1s against the package insert.
Summary
Weekly dual GLP-1 and GIP agonist, approved as Mounjaro (type 2 diabetes) and Zepbound (obesity). Titration goes from 2.5 mg to 15 mg per week, rising every four weeks. Effect and adverse event data come from the SURPASS and SURMOUNT programs.
Quick reference
- Route
- Subcutaneous injection, 1×/week.
- Titration
- From 2.5 mg to 15 mg per week, rising every 4 weeks.
- Measure
- mg-to-unit conversions covering 5, 10, 15, 40 and 60 mg vials.
- Status
- Approved — Mounjaro (type 2 diabetes) and Zepbound (obesity).
Titration ladder
| Mounjaro | Zepbound | |
|---|---|---|
| Active drug | Tirzepatide | Tirzepatide |
| FDA indication | Type 2 diabetes | Chronic weight management; OSA + obesity |
| First approved | May 2022 | November 2023 |
| Form sold by Lilly | Single-use pen | Single-use pen and vial |
| Titration ladder | 2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg weekly | 2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg weekly |
Tirzepatide Dosing Schedule
| Phase | Weeks | Dose | Notes |
|---|---|---|---|
| Phase 1 - Initiation | Weeks 1–4 | 2.5 mg 1×/week | Tolerability dose. Not a therapeutic dose for weight loss or HbA1c. |
| Phase 2 — Early maintenance | Weeks 5-8 | 5 mg 1×/week | First true maintenance dose. Most users feel reduced appetite here. |
| Phase 3 - Mid escalation | Weeks 9-12 | 7.5 mg 1×/week | Transitional. Hold longer if GI effects flare. |
| Phase 4 — Mid maintenance | Weeks 13-16 | 10 mg 1×/week | Second maintenance dose. Strong weight and HbA1c effects. |
| Phase 5 — High escalation | Weeks 17–20 | 12.5 mg 1×/week | Transitional. GI effects may briefly return. |
| Phase 6 — Maximum dose | Weeks 21+ | 15 mg 1×/week | Maximum FDA-approved dose. ~22.5% weight loss at 72 weeks in SURMOUNT-1. |
Tirzepatide Reconstitution Guide
| Vial | BAC water added | Concentration | 2.5 mg | 5 mg | 7.5 mg | 10 mg | 15 mg |
|---|---|---|---|---|---|---|---|
| 5 mg | 1.0 mL | 5 mg/mL | 0.50 mL / 50 u | 1.00 mL / 100 u | — | — | — |
| 10 mg | 1.0 mL | 10 mg/mL | 0.25 mL / 25 u | 0.50 mL / 50 u | 0.75 mL / 75 u | 1.00 mL / 100 u | — |
| 10 mg | 2.0 mL | 5 mg/mL | 0.50 mL / 50 u | 1.00 mL / 100 u | — | — | — |
| 15 mg | 1.5 mL | 10 mg/mL | 0.25 mL / 25 u | 0.50 mL / 50 u | 0.75 mL / 75 u | 1.00 mL / 100 u | 1.50 mL / split |
| 40 mg | 2.0 mL | 20 mg/mL | 0.125 mL / 12.5 u | 0.25 mL / 25 u | 0.375 mL / 37.5 u | 0.50 mL / 50 u | 0.75 mL / 75 u |
| 40 mg | 3.0 mL | 13.33 mg/mL | 0.188 mL / 18.8 u | 0.375 mL / 37.5 u | 0.563 mL / 56.3 u | 0.75 mL / 75 u | 1.125 mL / split |
| 60 mg | 3.0 mL | 20 mg/mL | 0.125 mL / 12.5 u | 0.25 mL / 25 u | 0.375 mL / 37.5 u | 0.50 mL / 50 u | 0.75 mL / 75 u |
Tirzepatide Timeline & What to Monitor
| Timeframe | What is reported | What the trials measured |
|---|---|---|
| Week 1–2 (2.5 mg) | Mild appetite reduction; some early nausea. | Baseline labs; no efficacy endpoint expected. |
| Week 4–8 (2.5 → 5 mg) | Steadier appetite suppression; first weight changes. | Early HbA1c shift in T2D; modest weight loss in obesity arms. |
| Week 12–16 (5 → 10 mg) | Most pronounced appetite and weight changes. | Roughly 10–15% weight loss in obesity arms by week 24. |
| Week 24+ (10 → 15 mg) | Weight loss plateaus or continues slowly. | −21.4% (10 mg) and −22.5% (15 mg) at 72 weeks (SURMOUNT-1). |
Storage and handling
The rules below apply to practically every lyophilized peptide in this reference. Where a compound has its own requirement, it appears in the table in the previous section.
- Lyophilized powder, sealed: refrigerator, between 2 and 8 °C, protected from light. Many tolerate room temperature for short transport periods, but that is tolerance, not a recommendation.
- After reconstitution: always refrigerated, between 2 and 8 °C. The stability window drops to days or a few weeks, depending on the compound.
- Never freeze after reconstituting. The freeze–thaw cycle degrades the peptide.
- Do not shake. Swirl the vial slowly. Shaking breaks the peptide chain.
- Bacteriostatic water down the wall of the vial, in a slow stream, not squirted directly onto the powder.
- Cloudy solution, with particles or a color change: discard. There is no recovery.
Lab tests and monitoring
This list is the one that appears recurrently in the source, with small variations by compound. It serves as a starting point for a conversation with a professional — not as a substitute for that conversation.
- Before starting: complete blood count, comprehensive metabolic panel, lipid panel, fasting glucose and HbA1c, TSH and free T4, blood pressure and resting heart rate.
- Depending on the compound: IGF-1 (GH axis), lipase and amylase (VIP and the incretin agonists), serum copper and ceruloplasmin (GHK-Cu and blends containing it), CRP.
- Reassessment: most protocols review between week 4 and week 8, and then every 8–12 weeks.
- Do not wait for the routine lab test in the face of abdominal pain, visual changes, a change in a mole, shortness of breath, asymmetric swelling or any new and persistent symptom. That is a reason to seek care, not a spreadsheet item.
Evidence limits
Data source: peptidedosingprotocols.com, accessed on September 3, 2026. Translation and organization in Portuguese are original work. No primary source (PubMed, trial registry, package insert) was checked in building this page — the check was against the secondary source, and that alone.