Peptide blend reconstitution math

Last updated: June 2026 · Reviewed June 2026 · Built by the InjectBuddy team

How many units is a 250/250 mcg BPC-157 + TB-500 blend? Reconstitution maths and draw chart

Q: How many units is a 250/250 mcg blend from a single dual-peptide vial?

With a 1:1 dual-peptide vial (e.g. 5 mg BPC-157 plus 5 mg TB-500 in 2 mL of water), the total concentration is 5,000 mcg/mL. To deliver 250 mcg of each peptide you need 500 mcg total: 500 divided by 5,000 = 0.10 mL = 10 units in a single draw. Non-1:1 ratio vials cannot hit the 250/250 split in one draw, so always read the label.

A 250 mcg BPC-157 + 250 mcg TB-500 blend has no single unit answer — it depends on concentration. With two matched 5 mg vials each mixed with 2 mL of bacteriostatic water, each 250 mcg draw is 10 units, so the blend is 20 units total; at 1 mL of water it is 10 units total. This guide works through the reconstitution maths, a units-by-BAC-water chart for common vial sizes, worked examples for both separate and dual-peptide vials, and answers the questions people ask most.

Key takeaways

Units depend on concentration: vial size (mg) ÷ bacteriostatic water (mL).
Two matched vials → each 250 mcg half draws to the same mark; add them.
A 1:1 dual-peptide vial → one draw delivers both peptides together.
Skip the arithmetic with the BPC-157 + TB-500 blend calculator — enter your vials and read the combined units.

What "250/250 blend units" actually asks

The phrase covers a specific, common setup: a combined dose of 250 mcg BPC-157 and 250 mcg TB-500 drawn into one insulin syringe, and how many units that is on a U-100 barrel. The answer is never fixed — it depends on how concentrated your peptide is, set by the vial size in milligrams and the bacteriostatic water you added.

Two physical arrangements are meant by "blend":

Two separate vials — a BPC-157 vial and a TB-500 vial, each reconstituted on its own, drawn one after the other into the same syringe.
One dual-peptide vial — a single vial holding both peptides as a lyophilised powder, reconstituted once, drawn once.

Both BPC-157 and TB-500 are preclinical research peptides: their tissue-repair effects are studied mostly in animals, and neither has established human dosing. The figures here are arithmetic conversions only, not a protocol — see the safety note at the end.

How this is calculated (units = mL × 100)

Every result on this page comes from two steps. First, the concentration of the reconstituted vial:

Concentration (mcg/mL) = vial content (mcg) ÷ bacteriostatic water added (mL)

Then the draw volume for your dose, converted to U-100 insulin units:

Draw volume (mL) = dose (mcg) ÷ concentration (mcg/mL), then units = draw volume (mL) × 100.

On a U-100 syringe, 1 mL = 100 units, so 0.10 mL = 10 units. New to the barrel? See U-100 syringe units explained and how to calculate injection volume. The conversion is identical for either peptide.

Two 250 mcg draws at 2,500 mcg/mL each: fill to 10 units, then continue to 20 units. The plunger stops well short of a 0.3 mL (30-unit) barrel's ceiling.

250/250 mcg from two separate vials

The most common case: a 5 mg BPC-157 vial and a 5 mg TB-500 vial, each reconstituted with the same water, drawn in sequence into one syringe. With equal doses and matched vials, the two draws are identical.

Worked example 1 — matched 5 mg vials, 2 mL

Both vials are 5 mg (5,000 mcg), each mixed with 2 mL bacteriostatic water. Concentration: 5,000 ÷ 2 = 2,500 mcg/mL each. BPC-157 draw: 250 ÷ 2,500 = 0.10 mL = 10 units. TB-500 draw: 250 ÷ 2,500 = 0.10 mL = 10 units. Draw BPC-157 first, then TB-500 into the same barrel. Combined: 0.20 mL = 20 units.

Worked example 2 — matched 5 mg vials, 1 mL

Both 5 mg vials mixed with 1 mL water = 5,000 mcg/mL each. Each 250 mcg draw: 250 ÷ 5,000 = 0.05 mL = 5 units. Combined: 0.10 mL = 10 units — the densest practical draw, hardest to read accurately.

Worked example 3 — matched 10 mg vials, 3 mL

Both 10 mg vials mixed with 3 mL water = 10,000 ÷ 3 = 3,333 mcg/mL each. Each 250 mcg draw: 250 ÷ 3,333 = 0.075 mL = 7.5 units. Combined: 0.15 mL = 15 units.

250/250 blend units by BAC water volume

This chart shows the units for a single 250 mcg draw at common reconstitution volumes. For a 250/250 blend from two matched vials, double the figure to get the combined total in the syringe.

Vial size	BAC water	Concentration	250 mcg draw	Both peptides (250/250)
5 mg	1 mL	5,000 mcg/mL	0.05 mL = 5 units	0.10 mL = 10 units
5 mg	2 mL	2,500 mcg/mL	0.10 mL = 10 units	0.20 mL = 20 units
5 mg	3 mL	1,667 mcg/mL	0.15 mL = 15 units	0.30 mL = 30 units
10 mg	2 mL	5,000 mcg/mL	0.05 mL = 5 units	0.10 mL = 10 units
10 mg	3 mL	3,333 mcg/mL	0.075 mL = 7.5 units	0.15 mL = 15 units
10 mg	5 mL	2,000 mcg/mL	0.125 mL = 12.5 units	0.25 mL = 25 units

Worked example 4 — reading the chart

Two matched 5 mg vials at 3 mL each (1,667 mcg/mL): each 250 mcg draw is 15 units, so the blend is 0.30 mL = 30 units — exactly filling a 0.3 mL barrel. 3 mL is the practical ceiling for a 5 mg / 0.3 mL setup.

The last column only applies when both vials are at the same concentration. If your vials differ in size or water volume, calculate each draw separately and add them.

When the two vials are not matched

If the vials differ, the two halves of the 250/250 dose draw to different unit marks, and you must add them. The combined total decides whether the dose fits your syringe.

Worked example 5 — mismatched concentrations

BPC-157: 5 mg + 2 mL = 2,500 mcg/mL. TB-500: 10 mg + 5 mL = 2,000 mcg/mL. BPC-157 draw: 250 ÷ 2,500 = 0.10 mL = 10 units. TB-500 draw: 250 ÷ 2,000 = 0.125 mL = 12.5 units. Combined: 22.5 units (0.225 mL).

22.5 units is awkward to read on a 0.3 mL syringe. The fix for any ugly fraction is to reconstitute both vials to the same concentration so each half draws to a round mark — see how much BAC water should I add?

250/250 mcg from one dual-peptide vial

Some suppliers sell one vial holding both peptides — e.g. 5 mg BPC-157 + 5 mg TB-500 as a combined 10 mg of powder. You reconstitute once and draw once, because both peptides are in solution together at a fixed ratio.

Worked example 6 — 1:1 dual vial

Dual vial: 5 mg BPC-157 + 5 mg TB-500 (10 mg total), mixed with 2 mL water. Total concentration: 10,000 ÷ 2 = 5,000 mcg/mL combined — which is 2,500 mcg/mL of each peptide in a 1:1 ratio. For 250 mcg of each you need 500 mcg total: 500 ÷ 5,000 = 0.10 mL = 10 units, in one pull. One 10-unit draw delivers the full 250/250.

Worked example 7 — 2:1 dual vial

A 2:1 vial holds 10 mg BPC-157 + 5 mg TB-500 (15 mg) in 3 mL = 5,000 mcg/mL total. Drawing 250 mcg of TB-500 (one-third of the mix, so 750 mcg total) = 15 units — but that delivers 500 mcg BPC-157, not 250. Non-1:1 vials cannot hit 250/250 in one draw; read the label.

With a fixed-ratio dual vial you cannot dose the two peptides independently. Drawing both together is the approach in the peptide blend calculator guide.

Checking your draw fits the syringe

At typical concentrations a 250/250 blend fits a 0.3 mL (30-unit) syringe, since the combined draws above run 10 to 30 units. Two checks: keep the combined total under your barrel capacity (over 30 units, step up to a 0.5 mL barrel or split), and make sure both halves land on readable marks (matched concentrations avoid awkward 7.5 or 12.5 draws). See 0.3 mL vs 0.5 mL vs 1 mL syringes, then confirm in the blend calculator.

So, how many units is a 250/250 mcg BPC-157 + TB-500 blend?

There is no fixed answer — units depend entirely on how concentrated your reconstituted vials are. With two matched 5 mg vials and 2 mL of bacteriostatic water each (2,500 mcg/mL), each 250 mcg draw is 10 units and the combined 250/250 blend is 20 units. At 1 mL of water per vial (5,000 mcg/mL), each draw is 5 units, giving 10 units combined. The formula is: concentration = vial mcg divided by water mL; units = (dose divided by concentration) multiplied by 100. Skip the arithmetic and enter your vial details directly into the BPC-157 + TB-500 blend calculator for an instant result.

FAQs

How many units is a 250/250 mcg BPC-157 + TB-500 blend?

It depends on concentration. Two matched 5 mg vials at 2 mL each (2,500 mcg/mL) give 10 units per peptide, 20 units combined. At 1 mL each (5,000 mcg/mL) it is 5 units each, 10 units combined. Always compute from your own vial size and water volume.

Do I draw BPC-157 and TB-500 separately or together?

Two separate vials: draw each in sequence into the same syringe (BPC-157 to its mark, then TB-500 up to the combined mark). One dual-peptide vial: reconstitute once and draw both together in a single pull, since they are already in solution at a fixed ratio.

What if my combined draw is an awkward number like 22.5 units?

That happens when the two vials sit at different concentrations, so each 250 mcg half draws to a different mark. Reconstitute both to the same concentration so each half lands on a round unit — 5 mg + 2 mL on both gives 10 units each, 20 total.

Is a 250/250 mcg dose safe?

BPC-157 and TB-500 are preclinical research peptides with no established human dosing from controlled trials. This page only converts mcg into syringe units; it is not a claim that 250/250 mcg is safe or effective. Speak to a qualified clinician before using anything injectable.

How many units is a 250/250 mcg blend from a single dual-peptide vial?

With a 1:1 dual-peptide vial (e.g. 5 mg BPC-157 + 5 mg TB-500 in 2 mL of water), the total concentration is 5,000 mcg/mL. To deliver 250 mcg of each peptide you need 500 mcg total: 500 divided by 5,000 = 0.10 mL = 10 units in a single draw. Non-1:1 ratio vials cannot hit the 250/250 split in one draw, so always read the label.

Sources

Duzel A, Vlainic J, Antunovic M, et al. Stable gastric pentadecapeptide BPC 157 in the treatment of colitis and ischemia and reperfusion in rats: New insights. World J Gastroenterol. 2017;23(48):8465-8488. PMID: 29358856. pmc.ncbi.nlm.nih.gov/articles/PMC5752708.
Goldstein AL, Hannappel E, Kleinman HK. Thymosin beta4: actin-sequestering protein moonlights to repair injured tissues. Trends Mol Med. 2005;11(9):421-429. PMID: 16099219. pubmed.ncbi.nlm.nih.gov/16099219.
U.S. Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks (Category 2 substances nominated under sections 503A/503B). www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks.
U.S. Pharmacopeia. General Chapter <797> Pharmaceutical Compounding - Sterile Preparations: standards for preparing injectable sterile medications. www.usp.org/compounding/general-chapter-797.
DailyMed (U.S. National Library of Medicine). HUMULIN R - insulin human injection, solution: FDA-approved label stating 100 units per mL (U-100). dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=9ec3e28a-cea9-4e45-9057-e5bf8e37014c.

This guide is for general educational purposes only and does not constitute medical advice. Always follow your prescriber's specific instructions.