How much bacteriostatic water do I add to a 1 mg Follistatin-344 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 1 mg vial is 500 mcg/mL, so every 10 units on a U-100 insulin syringe holds 50 mcg. With 1 mL it is 1 mg/mL (100 mcg per 10 units). With 3 mL it is 333.3 mcg/mL (33.333 mcg per 10 units). With 5 mL it is 200 mcg/mL (20 mcg per 10 units).

How many units is 100 mcg of Follistatin-344 from a 1 mg vial?

With 2 mL of water the vial is 500 mcg/mL, so 100 mcg is 0.2 mL, or 20 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 100 mcg draws are in a 1 mg Follistatin-344 vial?

10 (1 mg ÷ 100 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.

Follistatin-344 1 mg Reconstitution: BAC Water & Units

Short answer: 2 mL of bacteriostatic water in a 1 mg Follistatin-344 vial makes 500 mcg/mL. On a U-100 insulin syringe (1 mL = 100 units), every 10 units then holds 50 mcg. More water gives a weaker solution and a bigger draw for the same amount; the amount in the vial stays 1 mg.

Water volume chart for a 1 mg vial

1 mg Follistatin-344 vial, U-100 insulin syringe.
Water added	Concentration	Per 10 units	Per 1 unit
1 mL	1 mg/mL	100 mcg	10 mcg
2 mL	500 mcg/mL	50 mcg	5 mcg
3 mL	333.3 mcg/mL	33.333 mcg	3.333 mcg
5 mL	200 mcg/mL	20 mcg	2 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 1 mg vial.
Water added	50 mcg	100 mcg	200 mcg
1 mL	5 units	10 units	20 units
2 mL	10 units	20 units	40 units
3 mL	15 units	30 units	60 units
5 mL	25 units	50 units	100 units

A 1 mg vial holds 20 draws of 50 mcg, 10 draws of 100 mcg, 5 draws of 200 mcg, no matter how much water you add.

How far a 1 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 (500 mcg/mL). Example amounts only, not doses.

1 mg vial: draws, volume and units per example amount.
Amount per draw	Draws per vial	Volume per draw	Units per draw
25 mcg	40	0.05 mL	5 units
50 mcg	20	0.1 mL	10 units
100 mcg	10	0.2 mL	20 units
200 mcg	5	0.4 mL	40 units
400 mcg	2.5	0.8 mL	80 units

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

The math

Concentration. 1 mg ÷ 2 mL = 500 mcg/mL
Volume to draw. amount ÷ 500 mcg/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 Follistatin-344 guide.

Follistatin-344 1 mg reconstitution: how much water and how many units

Water volume chart for a 1 mg vial

Syringe units by amount

How far a 1 mg vial goes

The math

Frequently asked questions