How many units is 5 mg of tirzepatide?

It depends on exactly one thing: the concentration printed on your vial. Here it is at the 4 strengths compounded tirzepatide usually comes in, and drawn on the barrel.

At 5 mg/mL, 5 mg is 100 units (1 mL). At 10 mg/mL, 5 mg is 50 units (0.5 mL). At 20 mg/mL, 5 mg is 25 units (0.25 mL). At 40 mg/mL, 5 mg is 12.5 units (0.125 mL).

5 mg of tirzepatide, by vial concentration. U-100 insulin syringe.
Vial says	Which is	mL	Units	Syringe
5 mg / 1 mL 10 mg / 2 mL 15 mg / 3 mL	5 mg/mL	1	100	100-unit
10 mg / 1 mL 20 mg / 2 mL 30 mg / 3 mL 50 mg / 5 mL	10 mg/mL	0.5	50	50-unit
20 mg / 1 mL 40 mg / 2 mL 60 mg / 3 mL	20 mg/mL	0.25	25	30-unit
40 mg / 1 mL 80 mg / 2 mL	40 mg/mL	0.125	12.5	30-unit

What that looks like on the barrel

5 mg/mL → 100 units on a 100-unit syringe

10 mg/mL → 50 units on a 50-unit syringe

20 mg/mL → 25 units on a 30-unit syringe

40 mg/mL → 12.5 units on a 30-unit syringe

About this dose

Weeks 5–8. Weeks five to eight, and the first dose that's meant to do something. A lot of people stay here for months. The comfortable concentrations are 10 and 20 mg/mL (50 and 25 units). At 5 mg/mL you're filling a whole 100-unit syringe — it works, but it leaves you nowhere to go at 7.5.

Check it yourself

The whole sum is units = dose ÷ concentration × 100. For this dose at 5 mg/mL: 5 ÷ 5 × 100 = 100. If your vial isn't marked in mg/mL, the concentration is the vial's total milligrams divided by the water that went in — a 10 mg vial with 2 mL of water is 5 mg/mL.

Not one of those concentrations?

Tirzepatide vial → unitsU-100 syringe

Vial strength mg

Water you added mL

Your dose mg

Syringe

—

Fill in all three boxes.

Common setups:

← 2.5 mg 7.5 mg →

Other doses: 2.5 mg · 7.5 mg · 10 mg · 12.5 mg · 15 mg. The whole ladder, with every dose at every strength: the tirzepatide chart. Going the other way — you drew a number of units and want the milligrams — is here. And if the vial isn't tirzepatide at all, mg to units works for anything.