Tirzepatide (10 mg Vial) Dosage Protocol
Tirzepatide is a dual GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 receptor agonist. It is the active compound in FDA-approved Mounjaro (T2D) and Zepbound (obesity). Phase 3 SURMOUNT trials showed mean weight loss of ~20–22% of body weight over 72 weeks.
⚡ Quickstart Highlights
Dosing & Reconstitution Guide
Route: Subcutaneous | Frequency: Once weekly (same day each week)
| Phase | Weekly Dose | U-100 Units | Volume (mL) |
|---|---|---|---|
| Weeks 1–4 | 2.5 mg | 50 units | 0.50 mL |
| Weeks 5–8 | 5.0 mg | 100 units | 1.0 mL (split sites) |
| Weeks 9–12 | 7.5 mg | 150 units | 1.5 mL (split sites) |
| Weeks 13–16 | 10 mg | 200 units | 2.0 mL (split sites) |
| Weeks 17–20 | 12.5 mg | 250 units | 2.5 mL (split sites) |
| Weeks 21+ | 15 mg (max) | 300 units | 3.0 mL (split sites) |
Reconstitution Steps
- Draw 2.0 mL bacteriostatic water.
- Inject slowly down the inside glass wall; avoid foaming.
- Gently swirl until dissolved. Do not shake.
- Label with date. Refrigerate at 2–8°C, use within 28 days.
Supplies Planning
| Item | 12 Weeks | 24 Weeks |
|---|---|---|
| Tirzepatide vials (10 mg each) | 3 vials | 6 vials |
| Insulin syringes (U-100, 1 mL) | 12–24 | 24–48 |
| Bacteriostatic water (10 mL) | 2 × 10 mL | 3 × 10 mL |
| Alcohol swabs | 1 × 100-pack | 1–2 × 100-pack |
Mechanism of Action
Tirzepatide is a single synthetic peptide that acts as an agonist at both GIP and GLP-1 receptors — a so-called 'twincretin.' Both receptors are expressed in pancreatic β-cells and in the central nervous system. GIP receptor activation provides additive effects on insulin secretion and may improve insulin sensitivity in adipose tissue; combined with GLP-1 receptor agonism, the dual action produces greater appetite suppression and weight loss than GLP-1 receptor agonism alone.
Tirzepatide also appears to shift adipose tissue metabolism, promoting fat oxidation over storage. Unlike earlier incretin therapies, its unique GIP co-activation produces less nausea at equivalent weight-loss efficacy, due to differential GLP-1 receptor dose curves.
Research Findings & Safety Profile
- SURMOUNT-1 (NEJM, 2022): mean 20.9% body weight reduction at 72 weeks on 15 mg vs 3.1% placebo.
- SURMOUNT-2 (T2D, NEJM 2023): 15.7% weight loss; HbA1c reduction of 2.4 percentage points.
- Outperformed semaglutide 1 mg for HbA1c and weight reduction in SURPASS-2 head-to-head trial.
- Common adverse effects: nausea, diarrhea, vomiting, constipation — predominantly during dose escalation.
- Rare events: pancreatitis, hypoglycemia (particularly with sulfonylureas), gallbladder disease.
- FDA-approved: Mounjaro (T2D, 2022), Zepbound (obesity, 2023).
Storage
| State | Temperature | Duration | Notes |
|---|---|---|---|
| Lyophilized | −20°C (−4°F) | Up to 24 months | Dry, dark conditions |
| Reconstituted | 2–8°C (35–46°F) | Up to 28 days | Avoid freeze-thaw |