Tirzepatide Dosage & Reconstitution Guide

Reconstitution

Tirzepatide ships as a freeze-dried (lyophilized) powder that has to be mixed with bacteriostatic water before use. Draw 2 mL of bacteriostatic water into a syringe and add it to a 10 mg vial, letting the stream run down the inside wall of the glass rather than blasting the powder directly. Swirl gently — never shake — until the solution is clear, then keep it refrigerated.

Worked example. 2 mL into a 10 mg vial gives a concentration of 5 mg/mL (5000 mcg/mL). A 5 mg dose then works out to 1 mL = 100 units on a U-100 insulin syringe. Scale the water volume up or down to make your target dose land on an easy-to-read mark (1 unit = 0.01 mL).

1. Wipe both vial stoppers (peptide and bacteriostatic water) with an alcohol swab and let them dry.
2. Draw 2 mL of bacteriostatic water into a syringe.
3. Inject it slowly against the inside wall of the peptide vial.
4. Swirl gently until fully dissolved; do not shake.
5. Label the vial with the contents, concentration, and date, and store it in the refrigerator.

Dosing schedule

Timing & cycling

Inject subcutaneously once weekly on the same day each week, at any time of day, with or without food; the day of the week can be changed as long as doses are at least 3 days apart.

Cycle length. Used continuously as an ongoing chronic therapy rather than in cycles; weight tends to return after stopping.

Storage & handling

Keep the lyophilized (unmixed) vial refrigerated at 2–8 °C (36–46 °F) in a dry, dark place — it tolerates short periods at room temperature during shipping. Once reconstituted, store it at 2–8 °C, never frozen, and use it within about 2–4 weeks (sooner if the solution turns cloudy or discolored). Swab the stopper before every draw and use a fresh needle each time.

Supplies you'll need

• Tirzepatide vials — about 12 for an 8-week run at the upper dose
• Bacteriostatic water — 2 mL per vial (a 10–30 mL multi-dose bottle covers several vials)
• U-100 insulin syringes (0.3–0.5 mL / 30–50 unit barrels are easiest to read) — roughly 8 for 8 weeks, plus spares
• Alcohol swabs — one per injection and one per vial draw
• Sharps container for safe needle disposal

Key points

• It is a dual GIP/GLP-1 receptor agonist, which distinguishes it from single-pathway GLP-1 drugs like semaglutide and appears to give it an edge on weight loss in head-to-head trials (SURMOUNT-5).
• A significant portion of weight lost can be muscle; prioritize adequate protein and resistance training to protect lean mass.
• Escalate the dose only after at least 4 weeks and only when side effects are tolerable; there is no benefit to rushing the titration.
• The 2.5 mg starting dose is a non-therapeutic ramp-in step, not a treatment dose.
• The FDA drug (Mounjaro/Zepbound) is manufactured to pharmaceutical standards; research-chemical vials are unregulated and labeled not for human consumption.

What to monitor

Track GI tolerance, blood glucose (especially with insulin or sulfonylureas), weight and lean mass, and signs of pancreatitis or gallbladder disease. Contraindicated with a personal or family history of medullary thyroid carcinoma (MTC) or MEN 2.

Legal & prescription status

Prescription-only in the US. FDA-approved as Mounjaro (type 2 diabetes, 2022) and Zepbound (chronic weight management 2023; obstructive sleep apnea 2024). Compounded and 'research chemical' versions are not FDA-approved and are sold labeled 'not for human consumption.'

References

1. FDA Prescribing Information (Mounjaro USPI)
2. DailyMed - Mounjaro (tirzepatide) label
3. NEJM - SURPASS-2: Tirzepatide vs Semaglutide
4. PubMed - SURMOUNT-1: Tirzepatide for Obesity