Dual GLP-1/GIP Agonist

Tirzepatide Dosage Calculator & Guide

A dual-agonist option for weight management and blood sugar control. Calculate your dose and follow the step-up schedule from 2.5 mg to 15 mg.

Updated April 2026·5 min read·For educational purposes only

Tirzepatide at a Glance

Also Known As
Mounjaro, Zepbound, LY3298176
Developer
Eli Lilly
Mechanism
GLP-1 / GIP
Injection Frequency
Once Weekly
Common Vial Sizes
5 mg, 10 mg, 15 mg
Storage (Reconstituted)
Refrigerate, 4-6 weeks
Route
Subcutaneous
Half-Life
~5 days

Tirzepatide Dosage Calculator

Pre-filled with typical tirzepatide values. Adjust to match your vial and protocol.

mg
mL
mg
units
Draw To
-- IU
Volume
-- mL
Doses / Vial
--
Enter your values above to see your results in plain English.

Open Full Calculator with Syringe Visualization →

What Is Tirzepatide?

Tirzepatide is a first-in-class dual-agonist peptide developed by Eli Lilly that targets both GLP-1 and GIP (glucose-dependent insulinotropic polypeptide) receptors. It is approved as Mounjaro for type 2 diabetes and as Zepbound for chronic weight management.

The dual-agonist approach differentiates tirzepatide from single-agonist peptides like semaglutide. By activating both GLP-1 and GIP pathways, tirzepatide enhances insulin secretion, improves insulin sensitivity, reduces glucagon levels, slows gastric emptying, and modulates appetite through complementary mechanisms. Clinical trial data (SURMOUNT and SURPASS programs) demonstrated substantial weight reduction and metabolic improvements.

Important: Tirzepatide has not been approved by the FDA for general consumer use. The information on this page is for educational and research purposes only. Always consult a qualified healthcare provider before using any peptide.

Tirzepatide Dosing Protocol

Below are common dosing protocols for tirzepatide based on available research and community experience:

ProtocolDoseNotes
Weeks 1-42.5 mgStarting dose; establish tolerability
Weeks 5-85.0 mgFirst escalation
Weeks 9-127.5 mgSecond escalation
Weeks 13-1610.0 mgThird escalation
Weeks 17-2012.5 mgFourth escalation (if tolerated)
Week 21+15.0 mgMaximum approved dose
Tip: Use the calculator above to recalculate your syringe units whenever you adjust your dose. Bookmark this page for quick reference.

Ready to calculate? Use the calculator above or our full calculator with syringe visualization.

How to Reconstitute Tirzepatide

Tirzepatide comes as a lyophilized (freeze-dried) powder that must be reconstituted with bacteriostatic water before use. The process is standard for all peptides:

For a detailed step-by-step guide with visuals, see our complete peptide reconstitution guide.

Tirzepatide Side Effects

Understanding potential side effects helps you use tirzepatide more safely. Most side effects are dose-dependent and may improve over time.

Common Side Effects

Less Common Side Effects

If you experience severe or persistent side effects, discontinue use and contact your healthcare provider.

How to Store Tirzepatide

Before reconstitution: Store lyophilized (powder) tirzepatide in a cool, dry place away from direct sunlight. Refrigeration is ideal for long-term storage of unreconstituted peptides.

After reconstitution: Store the reconstituted vial upright in a refrigerator at 36-46°F (2-8°C). Do not freeze. The solution typically remains stable for 4-6 weeks. Always swab the vial stopper with an alcohol pad before each use.

Tirzepatide Dosing Tips

Because tirzepatide doses range from 2.5 mg to 15 mg, reconstitution math can vary significantly depending on your current dose. At lower doses (2.5-5 mg) with a 5 mg vial, you may get multiple doses per vial. At higher doses (10-15 mg), you may need larger vials or multiple vials per dose.

A common approach is to use 2 mL of BAC water per 5 mg vial, giving a concentration of 2.5 mg/mL. For a 2.5 mg dose, you would draw 1 mL (100 units). For a 5 mg dose, you would use the entire vial. Adjust the calculator above to match your specific vial size and target dose.

Tirzepatide FAQ

How is compounded tirzepatide different from Mounjaro?+
Mounjaro is the branded, FDA-approved pen injector manufactured by Eli Lilly. Compounded tirzepatide contains the same active molecule but comes as lyophilized powder requiring reconstitution with bacteriostatic water. The dosing and administration are the same once reconstituted.
Can I switch from semaglutide to tirzepatide?+
Many people do transition between these peptides. The typical approach is to start tirzepatide at the lowest dose (2.5 mg) regardless of your previous semaglutide dose, then titrate up as tolerated. Consult your healthcare provider for a personalized transition plan.
What's the maximum dose of tirzepatide?+
The maximum FDA-approved dose is 15 mg per week. Clinical trials studied doses up to 15 mg. Dose escalation should be gradual (every 4 weeks minimum) and guided by tolerability and clinical response.
How should I time my tirzepatide injection?+
Tirzepatide can be administered at any time of day, with or without food. Many people choose to inject on the same day each week for consistency. If you change your injection day, ensure at least 3 days have passed since your last dose.
Is tirzepatide more effective than semaglutide?+
Head-to-head clinical trials (SURPASS-2) showed tirzepatide produced greater reductions in body weight and HbA1c compared to semaglutide 1mg. However, individual responses vary and the best choice depends on your specific situation, tolerability, and medical history.

Other Peptide Calculators

Looking for a different peptide? Each calculator is pre-filled with standard dosing values.