Tirzepatide

Metabolic & weight FDA-approved drug

GIP/GLP-1 dual receptor agonist · also known as Mounjaro, Zepbound

For reference only — not medical advice. Figures are commonly reported values compiled from published sources and may be wrong or out of date. Many compounds listed are not approved for human use. Talk to a licensed clinician before using any compound.

Tirzepatide is a dual agonist that activates both the GIP and GLP-1 receptors. The combined incretin action is studied for metabolic and weight-related endpoints, with once-weekly dosing and gradual escalation.

Commonly reported dosing (50 mg vial)

Reconstituted with 2.5 mL → 20 mg/mL.

Also sold in 5 mg, 10 mg, 15 mg, 20 mg, 30 mg, 40 mg, 60 mg, 80 mg, 90 mg, 100 mg vials.

Phase	Dose	Volume	U-100 units
Starting Weeks 1-4	2.5 mg	0.125 mL	12.5
Standard Weeks 5-8	5 mg	0.25 mL	25
Higher Weeks 13-16 in the studied schedule	10 mg	0.5 mL	50

Frequency: Once weekly, subcutaneous · Half-life: ~5 days

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Commonly reported dose escalation

Weeks	Dose	Volume	U-100 units
Weeks 1-4	2.5 mg	0.125 mL	12.5
Weeks 5-8	5 mg	0.25 mL	25
Weeks 9-12	7.5 mg	0.375 mL	37.5
Weeks 13-16	10 mg	0.5 mL	50
Weeks 17-20	12.5 mg	0.625 mL	62.5
Week 21+	15 mg	0.75 mL	75

Higher steps may need a larger vial or more than one draw. Escalation schedules vary; dosing decisions belong to a licensed clinician.

Commonly reported reconstitution steps

Vials are usually brought to room temperature (about 15-20 minutes) first.
2.5 mL of bacteriostatic water is added slowly down the inside wall of the 50 mg vial.
The vial is swirled gently until clear, not shaken.
This gives 20 mg/mL. Mixed vials are typically labeled with the date and refrigerated.

Storage

Before mixing: Sealed vials are commonly stored refrigerated (2-8 °C) and protected from light, or frozen for long-term storage.

After mixing: Reconstituted solution is commonly kept refrigerated (2-8 °C), protected from light, and not frozen.

Commonly used within 28 days of mixing.

How it works

Simultaneous GIP and GLP-1 receptor activation enhances insulin sensitivity and secretion, slows gastric emptying, and reduces appetite through complementary pathways.

Researched for

In SURMOUNT-1 (72 weeks, adults with obesity), mean weight change was -15.0%, -19.5% and -20.9% with 5, 10 and 15 mg weekly versus -3.1% with placebo.
Dual incretin action studied for glycemic control and other metabolic endpoints.
Titration schedules in studies are designed around gastrointestinal tolerability.

Notes

Like other incretins, trial and label schedules begin at a low dose and escalate in steps.
GI symptoms most common during dose increases.
The label schedule is 2.5 mg weekly for 4 weeks, then 5 mg, with 2.5 mg steps after at least 4 weeks at each level; labeled maintenance amounts are 5, 10 or 15 mg, and 15 mg is the maximum.
Reconstitution volumes of 2-3 mL are commonly reported across 5-100 mg vials (for example 2.5 mL for 50 and 100 mg vials).
Brand-name pens and kits are pre-measured; the reconstitution figures here apply to vials that require mixing.
Figures here use a 50 mg vial with 2.5 mL (20 mg/mL), so every labeled step from 2.5 to 15 mg stays within a 1 mL syringe.