What is oxytocin peptide?
Oxytocin 10mg reconstitution comes down to one relationship: the mg in the vial, the BAC water you add, and the marks on a U-100 syringe. Oxytocin itself is a peptide hormone made naturally in the body. It is a nonapeptide, a chain of nine amino acids: Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly-NH2, with a bridge between the two cysteines that closes part of the chain into a ring.
The oxytocin peptide sold in research vials is synthetic, made to that same sequence. It is closely related in structure to vasopressin, which differs at two positions, but the two are separate compounds. This page makes no statement about what oxytocin does in the body; it covers the reconstitution arithmetic only.
How much BAC water for an oxytocin vial?
Research vials are usually labeled oxytocin 2mg, oxytocin 5mg or 10 mg of freeze-dried powder. The mg in the vial is fixed; the volume of bacteriostatic water you add sets the concentration. The chart shows micrograms per unit on a U-100 syringe for common water volumes.
| BAC water | 2 mg vial | 5 mg vial | 10 mg vial |
|---|---|---|---|
| 1 mL | 20 mcg/unit 2 mg/mL | 50 mcg/unit 5 mg/mL | 100 mcg/unit 10 mg/mL |
| 2 mL | 10 mcg/unit 1 mg/mL | 25 mcg/unit 2.5 mg/mL | 50 mcg/unit 5 mg/mL |
| 3 mL | 6.67 mcg/unit 0.667 mg/mL | 16.67 mcg/unit 1.667 mg/mL | 33.33 mcg/unit 3.333 mg/mL |
| 5 mL | 4 mcg/unit 0.4 mg/mL | 10 mcg/unit 1 mg/mL | 20 mcg/unit 2 mg/mL |
Each cell shows mcg per unit on a U-100 syringe (100 units = 1 mL) and the resulting concentration.
Read across a row to compare vial sizes at the same volume, or down a column to see how more water spreads the same powder thinner. A 10 mg vial is a lot of peptide for a small volume, which is why larger water volumes often appear in oxytocin 10mg reconstitution questions: they keep each unit from carrying a very large amount. The BAC water to peptide ratio guide explains the pattern.
Worked example: oxytocin 10mg reconstitution in 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 × 100 gives U-100 units. For example, if the amount you already have is 100 mcg, and a 10 mg oxytocin vial is mixed with 5 mL of BAC water:
The math: 10 mg ÷ 5 mL = 2 mg/mL (2,000 mcg/mL), which is 20 mcg per unit. 100 mcg ÷ 2,000 mcg/mL = 0.05 mL = 5 units on a U-100 syringe.
That amount is an arbitrary figure picked because it comes out clean. It is not a suggestion. For comparison, here is the same amount with an oxytocin 2mg vial mixed with 2 mL:
The math: 2 mg ÷ 2 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.
Keep everything in one unit before dividing: 1 mg = 1,000 mcg. Pharmaceutical oxytocin is often described in USP units rather than mg; those are a different kind of unit from syringe units, and this calculator does not convert between them. It works from the mg on your vial label only. The U-100 syringe units to mL guide explains what a syringe unit is.
Oxytocin nasal products and this calculator
Searches for oxytocin nasal come up often. This calculator covers one thing: syringe units on a U-100 syringe, calculated from a vial’s mg and the water you added. Nasal products are measured in a different way, by the volume each spray delivers, and that volume depends on the specific device. The calculator cannot convert a vial into sprays, and this page does not give spray instructions.
If you have a ready-made nasal product, the strength and directions are on its label. If you have a vial of powder, the chart and calculator above show how its concentration changes with water, and nothing more.
Oxytocin reconstitution notes from suppliers
Supplier instructions vary, so the label on your vial comes first. Some suppliers specify bacteriostatic water; others list sterile water. Some product sheets say oxytocin dissolves readily and should be swirled gently rather than shaken, and many list refrigeration after mixing along with a use-by period. Because an oxytocin 10mg vial holds a relatively large amount of a short peptide, some supplier sheets list a larger water volume for that size than for the 2 mg or 5 mg vials. That choice only changes the concentration, which the chart above already shows. Whatever volume you use, enter that exact figure in the calculator so the unit count matches what is in the vial. For general mixing steps, see the peptide reconstitution guide.
Is oxytocin FDA-approved?
Oxytocin is FDA-approved as an injection, sold as Pitocin, for specific obstetric use. That is a finished, labeled pharmaceutical product with a defined strength. Research-labeled vials of oxytocin powder sold online are not that product. They carry no approved strength, directions or quality standard, and they are labeled for research use only.
A correct calculation cannot confirm a vial’s identity, purity, sterility or stability. The numbers on this page are only as good as the label they start from. For other peptide calculators, browse the peptide library.
Oxytocin FAQ
How much BAC water do you add to an oxytocin 10mg vial?
There is no single required volume. The chart shows how 1, 2, 3 and 5 mL change the mcg per unit. Follow the product labeling for the diluent and volume, then enter the volume you used in the calculator.
Does this page give an oxytocin dose?
No. It converts an amount you already have into mL and U-100 syringe units for your vial and water volume. It does not recommend a dose, schedule or frequency.
Can the calculator work out oxytocin nasal sprays?
No. The calculator covers syringe units only. Nasal products are measured by the volume each spray delivers, which depends on the device and its label.
Are USP units the same as syringe units?
No. USP units describe a drug’s strength, while syringe units mark volume on a U-100 syringe, where 100 units equal 1 mL. This calculator works from the mg on the vial label.
Is a research oxytocin vial the same as Pitocin?
No. Pitocin is an FDA-approved oxytocin injection for specific obstetric use. Research-labeled vials of oxytocin powder are not that product.