What is Follistatin 344?
Follistatin 344 is a laboratory-made (recombinant) version of follistatin, a glycoprotein the body produces naturally. Follistatin binds and neutralizes several members of the TGF-beta family of signaling proteins, most notably activin and myostatin, which is why it appears in muscle and reproductive-biology research. The number 344 refers to one isoform, named for the length of its precursor chain in amino acids.
That makes follistatin 344 a full protein rather than a short peptide. It is many times larger than compounds like BPC-157 or Kisspeptin-10, and it is sold in much smaller amounts. You will see it labeled Follistatin 344, FST-344 or FS-344. This page covers only the reconstitution arithmetic; it does not describe any use in people.
How much BAC water for a Follistatin 344 1mg vial?
Most research vials are labeled follistatin 344 1mg. With so little powder, even a small volume of water produces a low concentration, so the useful water volumes are small too. The chart below shows micrograms per unit on a U-100 syringe for a 1 mg vial.
| BAC water | 1 mg vial |
|---|---|
| 0.5 mL | 20 mcg/unit 2 mg/mL |
| 1 mL | 10 mcg/unit 1 mg/mL |
| 1.5 mL | 6.67 mcg/unit 0.667 mg/mL |
| 2 mL | 5 mcg/unit 0.5 mg/mL |
Each cell shows mcg per unit on a U-100 syringe (100 units = 1 mL) and the resulting concentration.
Compare these figures with the tens of micrograms per unit you see for 5 mg or 10 mg peptide vials. Every extra half millilitre of water lowers the micrograms in each unit, and with a 1 mg vial the numbers are already small. The volumes shown only illustrate the arithmetic; the product labeling decides the diluent and volume. For a broader look at how volume choices work, see how to reconstitute peptides.
Worked example: follistatin 344 1mg in syringe units
The calculator runs three steps. Vial mg ÷ water mL gives the concentration. The amount you enter ÷ that concentration gives the volume in mL. Volume in mL × 100 gives U-100 units. For example, if the amount you already have is 100 mcg, and the vial is 1 mg with 1 mL of water added:
The math: 1 mg ÷ 1 mL = 1 mg/mL (1,000 mcg/mL), which is 10 mcg per unit. 100 mcg ÷ 1,000 mcg/mL = 0.1 mL = 10 units on a U-100 syringe.
The 100 mcg figure is arbitrary, chosen because a 1 mg vial in 1 mL gives a clean result. With a vial this small, always enter amounts in mcg. Because 1 mg = 1,000 mcg, entering the same number in mg would ask for more than the whole vial holds. The mg to mcg conversion guide covers the switch between units.
Why small vials need careful math
Small vials leave little room for error. A 1 mg vial holds 1,000 mcg in total, so a misplaced decimal point in the water volume or the amount changes the result dramatically. Three habits help:
- Enter the exact water volume you added, including decimals such as 0.5 or 1.5 mL, rather than rounding.
- Keep the amount in mcg so the numbers stay whole and readable.
- Read the unit count from the calculator, then confirm it against the syringe marks. On a U-100 syringe, 100 units = 1 mL and 1 unit = 0.01 mL, whatever the syringe capacity.
Smaller-capacity U-100 syringes such as 0.3 mL show the same units with wider spacing, which some people find easier to read at low volumes. The U-100 syringe units to mL guide explains how capacity and units relate.
Follistatin 344 reconstitution notes from suppliers
Proteins are generally more delicate than short peptides, and follistatin labeling often reflects that. Some suppliers specify swirling or rolling the vial gently rather than shaking, because agitation can damage protein structure. Some specify bacteriostatic water; others specify sterile water or a particular buffer solution. Storage temperature and how long a mixed vial is kept vary by product, so follow the label of the exact product and a qualified professional.
Bacteriostatic water contains 0.9% benzyl alcohol, which slows some bacterial growth but does not sterilize. An opened multi-dose vial is commonly dated and discarded within 28 days unless the manufacturer specifies a different date. If a label names saline or a buffer instead, the guide to BAC water vs saline for peptides explains how those liquids differ.
Regulatory status of Follistatin 344
Follistatin 344 is not an FDA-approved drug. Vials sold online are labeled for research use only and carry no approved labeling, so identity, purity, protein integrity and sterility depend on the supplier. With a recombinant protein, the label should state the amount of active protein, and products under the same name can differ in source, form and fill.
A correct calculation cannot confirm what is in a vial. It only relates the label amount, the water you added and the syringe marks. Other research compounds are listed in the peptide library.
Follistatin 344 FAQ
What is follistatin 344?
Follistatin 344 is a recombinant form of follistatin, a natural glycoprotein that binds activin and myostatin. The 344 names an isoform by the amino acid length of its precursor. Research-labeled vials are not FDA-approved.
How much BAC water goes in a follistatin 344 1mg vial?
There is no single correct amount. Small volumes are typical for a 1 mg vial, and the chart shows mcg per syringe unit for several of them. The product labeling decides the diluent and volume.
Should I enter follistatin amounts in mg or mcg?
Use mcg. A 1 mg vial holds 1,000 mcg in total, and working in mcg keeps the numbers readable and avoids decimal errors.
Why do some suppliers say not to shake follistatin?
Follistatin is a protein, and vigorous agitation can damage protein structure. Some suppliers specify gentle swirling instead. Follow the product labeling.
Is this a follistatin 344 dosage calculator?
It converts an amount you already have into mL and U-100 syringe units. It does not recommend or check any dose, schedule or frequency.