Medical Disclaimer

This website is for informational purposes only and does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before starting, changing, or stopping any medication or supplement. Dosage information reflects published FDA-approved labeling or publicly available clinical trial data — individual treatment decisions must be made by a licensed physician.

About tirzepatide

Tirzepatide is a dual GIP and GLP-1 receptor agonist approved for type 2 diabetes (Mounjaro) and chronic weight management (Zepbound). This chart shows the standard dose escalation protocol as outlined in the FDA-approved prescribing information.

Indication

Type 2 diabetes management (Mounjaro) and chronic weight management in adults with BMI ≥30 or ≥27 with weight-related comorbidity (Zepbound).

Standard Titration Schedule

Frequency: Once weekly, on the same day each week. Maximum approved dose: 15 mg once weekly.

Week / PhaseDoseAt 2.5 mg/mLAt 5 mg/mLNotes
Weeks 1–42.5 mg10 units
(2.5 mg/mL)
5 units
(5 mg/mL)
Initiation dose. Not intended for glycemic control. Taken to improve tolerability.
Weeks 5–85 mg20 units
(2.5 mg/mL)
10 units
(5 mg/mL)
First maintenance dose. Dose may be maintained for additional 4 weeks if not tolerated.
Weeks 9–127.5 mg30 units
(2.5 mg/mL)
15 units
(5 mg/mL)
Escalation step. GI side effects may increase temporarily.
Weeks 13–1610 mg40 units
(2.5 mg/mL)
20 units
(5 mg/mL)
Second maintenance dose. Many patients reach their target weight-loss response here.
Weeks 17–2012.5 mg50 units
(2.5 mg/mL)
25 units
(5 mg/mL)
Higher dose step for additional efficacy.
Week 21+15 mg60 units
(2.5 mg/mL)
30 units
(5 mg/mL)
Maximum approved dose. Continue only if clinically indicated.

Units shown assume a standard U-100 insulin syringe (100 units = 1 mL). Always confirm your vial concentration with your pharmacy.

Dose Calculator

Enter your prescribed dose and vial concentration to calculate how many units to draw.

mg ↔ Units Dose Calculator

Convert between milligrams and insulin-syringe units for compounded GLP-1 medications. Uses a standard U-100 syringe (100 units = 1 mL).

Units (U-100 syringe)100 units
Volume1.000 mL

2.5 mg at 2.5 mg/mL → 1.000 mL → 100 units on a U-100 (100-unit / 1 mL) insulin syringe

Always verify calculations with your prescribing provider or pharmacist before administering any medication. This calculator is for reference only.

Injection Sites

Abdomen

Fatty tissue of the abdomen, at least 2 inches from the navel.

  • Avoid injecting within 2 inches of your navel
  • Rotate injection sites within the abdomen each week
  • Fastest absorption site

Thigh

Outer or front of the thigh (upper/middle portion).

  • Use the outer front area, not the inner thigh
  • Good for self-injection, easy to see
  • Slightly slower absorption than abdomen

Upper arm

Back of the upper arm (triceps area).

  • Usually requires a caregiver or healthcare provider for injection
  • Avoid bony areas — use fatty tissue only
  • Pinch the skin if needed

Storage Instructions

  • Store unopened pens in the refrigerator (36°F–46°F / 2°C–8°C)
  • Do not freeze. Discard if frozen.
  • Keep away from light; store in original packaging
  • After first use, may store at room temperature (≤86°F / 30°C) for up to 21 days
  • Discard pen 21 days after first use, even if medication remains

Common Side Effects

Contact your healthcare provider if side effects are severe or persistent.

  • Nausea (most common, especially at dose increases)
  • Diarrhea
  • Vomiting
  • Constipation
  • Abdominal pain
  • Decreased appetite (also the therapeutic goal)
  • Injection site reactions

Frequently Asked Questions

Q

How many units is 2.5 mg of tirzepatide?

It depends on the concentration of your vial. For compounded tirzepatide at 2.5 mg/mL: 10 units (0.1 mL). At 5 mg/mL: 5 units (0.05 mL). At 10 mg/mL: 2.5 units (0.025 mL). Use the dose calculator above to convert any dose for your specific concentration.
Q

What is the starting dose of tirzepatide?

The FDA-approved starting dose is 2.5 mg once weekly for 4 weeks. This is an initiation dose intended to improve tolerability — it is not expected to provide full therapeutic benefit. Your provider will then increase to 5 mg after 4 weeks.
Q

Can I skip the titration steps?

No. The titration schedule exists to reduce GI side effects (nausea, vomiting, diarrhea). Skipping steps increases the risk of intolerable side effects. Always follow your provider's instructions.
Q

What is the maximum dose of tirzepatide?

The maximum approved dose is 15 mg once weekly. Not all patients will need to reach the maximum dose — many achieve significant weight loss at 5 mg, 10 mg, or 12.5 mg.
Q

Is tirzepatide the same as semaglutide?

No. Tirzepatide (Mounjaro/Zepbound) is a dual GIP and GLP-1 receptor agonist. Semaglutide (Ozempic/Wegovy) is a GLP-1 receptor agonist only. Clinical trials suggest tirzepatide produces greater average weight loss, though individual responses vary.
Q

What if I miss a dose?

If a dose is missed, take it as soon as possible within 4 days of the missed dose. If more than 4 days have passed, skip the missed dose and resume on your next scheduled day. Do not take two doses in one day.

Primary Source

FDA / Clinical Source

Dosing information sourced from: https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/215866s000lbl.pdf