Tirzepatide Calculator
Built for compounded tirzepatide (Mounjaro/Zepbound). Select your vial, water volume, and titration dose to get exact syringe units. Full 6-step dosing chart included.
Vial size
BAC water added
Your concentration
5.00 mg/ml
Select your weekly dose
Select your weekly dose above to see how many units to draw.
Tirzepatide dosing chart
Pre-calculated syringe units for every titration dose at common vial/water setups. Higher doses require higher-concentration setups to stay within syringe capacity.
| Dose | Phase | 10mg + 1ml10 mg/ml | 10mg + 2ml5 mg/ml | 30mg + 2ml15 mg/ml | 30mg + 3ml10 mg/ml |
|---|---|---|---|---|---|
| 2.5 mg | Starting dose | 25 u | 50 u | 16.7 u | 25 u |
| 5 mg | Step 2 | 50 u | 100 u | 33.3 u | 50 u |
| 7.5 mg | Step 3 | 75 u | — | 50 u | 75 u |
| 10 mg | Step 4 | 100 u | — | 66.7 u | 100 u |
| 12.5 mg | Step 5 | — | — | 83.3 u | — |
| 15 mg | Maintenance | — | — | 100 u | — |
All values in syringe units (U-100). A dash means the dose exceeds syringe capacity at that concentration. Higher-dose phases need more concentrated solutions.
Standard titration schedule
Tirzepatide uses a 6-step escalation with 2.5 mg increases every 4 weeks. This is the schedule used in Syntho protocols, matching the FDA-approved Mounjaro/Zepbound titration.
Starting dose. GI side effects typically appear in the first 1-2 weeks and then ease.
First noticeable appetite suppression. Some patients see early weight changes.
Dual GIP/GLP-1 effect is fully engaged. Cravings reduce significantly.
Strong therapeutic dose. Many patients maintain here long-term.
Near-maximum. Only increase if 10 mg was well tolerated with room for more effect.
Maximum dose. Not all patients need to reach this level. Stay where efficacy and side effects balance.
10 mg is often enough. Clinical data shows strong efficacy at 10 mg for most patients. Escalating to 12.5 or 15 mg adds incremental benefit but also increases side effect risk. Find your balance.
How tirzepatide works
Tirzepatide is a dual GIP/GLP-1 receptor agonist. Unlike semaglutide (GLP-1 only), it activates both the glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors simultaneously.
This dual mechanism produces stronger appetite suppression and greater weight loss than single-target GLP-1 agonists. Clinical trials show 20-26% average body weight loss, compared to 15-17% with semaglutide. The trade-off is larger dose jumps (2.5 mg per step vs. fractional mg increases) and a longer total titration period (24+ weeks to reach maximum dose).
vs. Semaglutide
- Higher average weight loss (20-26% vs 15-17%)
- Dual receptor mechanism (GIP + GLP-1)
- Larger dose range (2.5-15 mg vs 0.25-2.4 mg)
- 6 titration steps vs 5
vs. Retatrutide
- FDA-approved (retatrutide is experimental)
- Dual agonist vs triple agonist (GIP + GLP-1 + glucagon)
- More clinical safety data available
- Steadier dose escalation (2.5 mg steps vs doubling)
Reconstituting tirzepatide
Same process as any peptide reconstitution. Clean workspace, room-temperature vials, inject BAC water against the glass wall, swirl gently. The key consideration for tirzepatide is concentration: higher doses (10-15 mg) need a more concentrated solution to keep the draw volume within syringe capacity.
Storage: Refrigerate at 2-8 degrees C. Stable for approximately 28 days with BAC water. Do not freeze. Label with date, concentration, and discard date.
Compounded vs. brand-name: The tirzepatide molecule is identical. Brand-name Mounjaro and Zepbound use pre-filled pens. Compounded tirzepatide comes as lyophilized powder in vials. This calculator is for the vial-based compounded form.