Tirzepatide Dosage Guide
Written by Alejandro Reyes
Founder & Lead Researcher
Reviewed by Peptide Nerds Editorial · Updated April 2026
Dosage overview
| Typical dose | 2.5 mg to 15 mg weekly |
| Frequency | Once weekly subcutaneous injection |
| Cycle length | Ongoing |
Dosing notes
Standard titration: 2.5 mg/week for weeks 1-4, then 5 mg for weeks 5-8, then 7.5 mg for weeks 9-12, then 10 mg for weeks 13-16, then 12.5 mg for weeks 17-20, then 15 mg maintenance. Not everyone needs 15 mg — many achieve good results at 10 or 12.5 mg with fewer side effects. Inject subcutaneously in abdomen, thigh, or upper arm. Rotate sites weekly.
FDA-approved indications
Tirzepatide is FDA-approved for: Type 2 diabetes (Mounjaro), chronic weight management (Zepbound).
Off-label use should only be pursued under the guidance of a licensed healthcare provider.
Important safety information
Dosage ranges listed above are based on published clinical trial protocols. Individual dosing should be determined by a qualified healthcare provider based on your specific health profile, goals, and response to treatment.
- Start at the lowest effective dose and titrate up gradually
- Monitor for side effects, especially during dose increases
- Do not exceed researched dose ranges without medical supervision
Interactive protocol guide
Step-by-step: your dosing schedule with exact syringe units, what supplies to buy, how to mix, and how to inject.
Tirzepatide Protocol Overview
Goal
Weight loss
Duration
24 weeks
Route
subcutaneous
Important before you start:
- Do not use if you have a personal or family history of medullary thyroid carcinoma or MEN 2.
- Monitor blood sugar closely if diabetic. Hypoglycemia risk increases with concurrent insulin.
- Severe GI symptoms (nausea, vomiting, diarrhea) may require slower titration.
Your dosing schedule
Based on a 10 mg vial mixed with 2 mL bacteriostatic water (5.00 mg/mL concentration). Using a U-100 insulin syringe.
Draw to here
50 units
on 100-unit syringe
1-4: 2.5 mg
Click a row to update
| When | Dose | Syringe units | Frequency | What to expect |
|---|---|---|---|---|
| 1-4 | 2.5 mg | 50 units | Once weekly | Starting dose. GI side effects are common but usually mild. |
| 5-8 | 5 mg | 100 units | Once weekly | First escalation. Stay here longer if side effects are significant. |
| 9-12 | 7.5 mg | 150 units | Once weekly | Continue titrating only if weight loss goals are not met. |
| 13-16 | 10 mg | 200 units | Once weekly | Significant appetite reduction expected at this dose. |
| 17-20 | 12.5 mg | 250 units | Once weekly | Optional step. Many users plateau at 10 mg. |
| 21-24 | 15 mg | 300 units | Once weekly | Maximum dose. Only if prior doses are well-tolerated. |
1-4: 2.5 mg
Starting dose. GI side effects are common but usually mild.
5-8: 5 mg
First escalation. Stay here longer if side effects are significant.
9-12: 7.5 mg
Continue titrating only if weight loss goals are not met.
13-16: 10 mg
Significant appetite reduction expected at this dose.
17-20: 12.5 mg
Optional step. Many users plateau at 10 mg.
21-24: 15 mg
Maximum dose. Only if prior doses are well-tolerated.
What you need for a 24-week Tirzepatide protocol
Tirzepatide vials (10 mg each)
Quantity: 21
Bacteriostatic water (30 mL vial)
Quantity: 2
Insulin syringes (U-100, 29ga)
Quantity: 24+ (one per injection, never reuse)
Alcohol prep pads
Quantity: 48+ (one for vial, one for skin)
Sharps container
Quantity: 1
Quantities based on 24-week protocol using 10 mg vials reconstituted with 2 mL BAC water each.
How to mix your Tirzepatide
Your concentration:
10 mg peptide + 2 mL water = 5.00 mg/mL (5000 mcg/mL)
- 1
Wash your hands
Wash with soap and water for 30 seconds. Dry completely.
- 2
Clean the vial tops
Wipe the rubber stopper on your Tirzepatide vial AND your bacteriostatic water vial with an alcohol swab. Let air dry for 10 seconds.
- 3
Draw 2 mL of bacteriostatic water
Using an insulin syringe, draw 2 mL (200 units on a U-100 syringe) of bacteriostatic water.
- 4
Inject water into the Tirzepatide vial
Hold the peptide vial at a 45-degree angle. Point the needle at the WALL of the vial, NOT directly onto the powder. Push the plunger slowly over 10-15 seconds. Let the water run down the inside wall.
- 5
Swirl gently to dissolve
Swirl the vial in a slow circular motion for 30-60 seconds. NEVER shake. If not fully dissolved, let it sit for 2-5 minutes and swirl again.
- 6
Refrigerate immediately
Store reconstituted peptide at 36-46 degrees F (2-8 degrees C). Good for 4-6 weeks refrigerated. Label the vial with the date you mixed it.
Common mistakes that ruin your peptide:
- Shaking the vial (breaks peptide bonds, reduces potency 30-50%)
- Spraying water directly on the powder (damages the peptide)
- Using sterile water instead of bacteriostatic water (no preservative, short shelf life)
- Leaving mixed peptide at room temperature (loses 10-20% potency per day)
How to inject Tirzepatide
Timing: Same day each week, any time of day
- 1Choose your injection site and rotate each time (at least 1 inch from the last site).
- 2Wipe the injection site with an alcohol prep pad. Let air dry completely.
- 3Draw your dose (check the dosing schedule above for exact syringe units).
- 4Pinch a fold of skin at the injection site.
- 5Insert the needle at a 45-90 degree angle into the pinched skin fold.
- 6Push the plunger slowly and steadily.
- 7Release the skin fold, then withdraw the needle.
- 8Do NOT rub the injection site. Light pressure with a cotton ball is fine if there is any blood.
- 9Dispose of the syringe immediately in your sharps container. Never recap or reuse.
Site rotation tip
Divide your preferred injection area into a mental grid. Move to a new spot each injection. For Abdomen and Thigh and Upper arm injections, alternate between sides (left/right) each time.
Research references
- Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1) — New England Journal of Medicine (2022) [PubMed]
- Tirzepatide vs Semaglutide for Weight Loss (SURMOUNT-5) — New England Journal of Medicine (2024) [PubMed]
- Tirzepatide in Patients with Obesity and Type 2 Diabetes (SURMOUNT-2) — Lancet (2023) [PubMed]
- Tirzepatide Once Weekly for Treatment of Obesity: Maintenance (SURMOUNT-4) — JAMA (2024) [PubMed]
- Tirzepatide vs Semaglutide in Type 2 Diabetes (SURPASS-2) — New England Journal of Medicine (2021) [PubMed]
- Tirzepatide Efficacy and Safety in Obesity: SURMOUNT-3 — Nature Medicine (2023) [PubMed]
Free Peptide Weight Loss Guide
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