How much bacteriostatic water do I add to a 5 mg VIP vial?

There is no single right amount. More water makes each draw bigger and easier to measure; less water keeps the volume small. With 2 mL, a 5 mg vial is 2.5 mg/mL, so every 10 units on a U-100 insulin syringe holds 250 mcg. With 1 mL it is 5 mg/mL (500 mcg per 10 units). With 3 mL it is 1.67 mg/mL (166.667 mcg per 10 units). With 5 mL it is 1 mg/mL (100 mcg per 10 units).

How many units is 50 mcg of VIP from a 5 mg vial?

With 2 mL of water the vial is 2.5 mg/mL, so 50 mcg is 0.02 mL, or 2 units on a U-100 syringe. With a different water volume the units change but the amount does not. The amount is an example for the math, not a recommendation.

How many 50 mcg draws are in a 5 mg VIP vial?

100 (5 mg ÷ 50 mcg), whatever volume of water you add. In practice a little is lost to the syringe dead space and the last drops in the vial.

VIP 5 mg Reconstitution: BAC Water & Units

Short answer: 2 mL of bacteriostatic water in a 5 mg VIP vial makes 2.5 mg/mL. On a U-100 insulin syringe (1 mL = 100 units), every 10 units then holds 250 mcg. More water gives a weaker solution and a bigger draw for the same amount; the amount in the vial stays 5 mg.

Water volume chart for a 5 mg vial

5 mg VIP vial, U-100 insulin syringe.
Water added	Concentration	Per 10 units	Per 1 unit
1 mL	5 mg/mL	500 mcg	50 mcg
2 mL	2.5 mg/mL	250 mcg	25 mcg
3 mL	1.67 mg/mL	166.667 mcg	16.667 mcg
5 mL	1 mg/mL	100 mcg	10 mcg

Syringe units by amount

The amounts below are examples to show the conversion, not doses. How much to take is a decision for you and your prescriber.

Units on a U-100 syringe from a 5 mg vial.
Water added	25 mcg	50 mcg	100 mcg
1 mL	under 2 units	under 2 units	2 units
2 mL	under 2 units	2 units	4 units
3 mL	under 2 units	3 units	6 units
5 mL	2.5 units	5 units	10 units

A 5 mg vial holds 200 draws of 25 mcg, 100 draws of 50 mcg, 50 draws of 100 mcg, no matter how much water you add.

How far a 5 mg vial goes

Draws per vial depend only on the amount per draw, not on the water. The volume and units columns use 2 mL of water (2.5 mg/mL). Example amounts only, not doses.

5 mg vial: draws, volume and units per example amount.
Amount per draw	Draws per vial	Volume per draw	Units per draw
12.5 mcg	400	0.005 mL	under 2 units
25 mcg	200	0.01 mL	under 2 units
50 mcg	100	0.02 mL	2 units
100 mcg	50	0.04 mL	4 units
200 mcg	25	0.08 mL	8 units

Real counts run a little lower: some liquid stays in the syringe and at the bottom of the vial.

The math

Concentration. 5 mg ÷ 2 mL = 2.5 mg/mL
Volume to draw. amount ÷ 2.5 mg/mL = mL
Syringe units. mL × 100 = units

For a different water volume or amount, the free peptide reconstitution calculator works backwards from the amount you want and suggests a water volume that lands on a clean syringe mark.

Half-life, time to peak and sources are on the main VIP (Vasoactive Intestinal Peptide) guide.

VIP 5 mg reconstitution: how much water and how many units

Water volume chart for a 5 mg vial

Syringe units by amount

How far a 5 mg vial goes

The math

Frequently asked questions