How to reconstitute TB-500

What reconstitution is

TB-500 arrives as a freeze-dried powder sealed in a vial. Powder cannot be measured in a syringe, so it has to be dissolved into a known volume of liquid first. The liquid used is bacteriostatic water, which is sterile water containing a preservative intended to limit microbial growth after the stopper has been pierced more than once.

The powder adds almost nothing to the final volume, so the water volume added is treated as the volume of solution that comes out. Concentration is then just the milligrams in the vial divided by the millilitres of water. That single division is the whole exercise. Draw volumes follow from it.

Reading the concentration table

The table above pairs the three vial sizes sold, 2, 5 and 10 mg, with the three water volumes commonly used, 1, 2 and 3 mL. Three points in it matter.

The same concentration can arrive from different starting points. A 10 mg vial in 2 mL and a 5 mg vial in 1 mL both give 5 mg/mL. A syringe cannot tell them apart. What differs is how many doses the vial holds, not how a dose is drawn.

More water does not weaken the dose. It spreads the same mass across more liquid. A 5 mg vial in 1 mL is 5 mg/mL; the same vial in 3 mL is 1.67 mg/mL. The second requires a much larger draw for the same milligram amount.

Some pairings give awkward figures. A 2 mg vial in 3 mL gives 0.67 mg/mL, and a 10 mg vial in 3 mL gives 3.33 mg/mL. Both are rounded recurring decimals. Choosing a water volume that divides the vial evenly avoids that entirely.

From concentration to a draw volume

Divide the dose in milligrams by the concentration in milligrams per millilitre. The result is the volume to draw.

The cleanest cases are the ones where the dose in milligrams equals the concentration figure, because the answer is 1 mL. A 10 mg vial in 2 mL is 5 mg/mL, so a 5 mg dose is 1 mL. A 5 mg vial in 2 mL is 2.5 mg/mL, so a 2.5 mg dose is 1 mL. A 2 mg vial in 2 mL is 1 mg/mL, so a 1 mg dose is 1 mL.

Insulin syringes are marked in units rather than millilitres. Once you have the draw volume in millilitres, convert it using the scale printed on your own syringe. A 1 mL U-100 barrel holds 1 mL when full, so any calculated volume larger than that will not fit in a single draw. That mechanical limit, not any biological reasoning, is often what decides how much water goes into a vial. A 2 mg vial in 3 mL is 0.67 mg/mL, and 2 mg of that solution exceeds one barrel.

What this page does not tell you

There is no reliable human pharmacokinetic data for TB-500. This site makes no claim about its half life, how long it takes to clear, or whether it accumulates with repeated administration. Spacing doses across days or weeks is outside what this arithmetic can support, and we do not supply it.

TB-500 is not approved by any regulator for human use. This page has no medical review behind it. It does not tell you what dose to use, what to expect, what adverse effects occur, or whether the compound works. The dose figures of 1, 2, 2.5 and 5 mg appear here only because they are the amounts seen in vendor listings. They are inputs to a division problem, nothing more.

What we do not know

We hold no reliable human pharmacokinetic data for TB-500, so this site makes no claims about its half life, how long it takes to clear, or how it accumulates. The arithmetic below concerns concentration and volume only.

This page answers arithmetic and handling questions. It does not tell you what dose to take, what to expect, or whether anything is appropriate for you, and there is no medical review behind it.

Common questions

How much bacteriostatic water do I add to a 5 mg TB-500 vial?

The table covers 1, 2 and 3 mL, giving 5 mg/mL, 2.5 mg/mL and 1.67 mg/mL. We do not tell you which to pick. The choice depends on the dose you intend to draw and whether that draw fits your syringe.

Does adding more water make the dose weaker?

No. The vial still contains the same mass of TB-500. More water lowers the concentration, so a given dose in milligrams is drawn as a larger volume of liquid. Nothing about the powder changes.

Why do two different combinations give the same concentration?

Concentration is milligrams divided by millilitres, and different pairs can share a quotient. A 10 mg vial in 2 mL and a 5 mg vial in 1 mL both give 5 mg/mL, so draw volumes are identical. The difference is how many doses each vial holds.

Can I use plain sterile water instead of bacteriostatic water?

This page does not answer that. The figures here assume bacteriostatic water, which carries a preservative intended for repeated stopper punctures. Whether a substitute is appropriate is a clinical question, and this page has no medical review behind it.

What is the half life of TB-500?

We hold no reliable human pharmacokinetic data for TB-500, so we make no claim about its half life, clearance or accumulation. Any specific figure quoted elsewhere goes beyond what can be verified. The arithmetic here concerns concentration and volume only.