Blending Calculator

Mixing dry peptides into a single shared vial sounds tidy but breaks dose control. Different peptides have different shelf lives, ideal pH ranges, and stability characteristics. Combining them into one solution makes it impossible to adjust one dose without touching the others, and any precipitation will affect everything in the vial.

The standard approach: reconstitute each peptide separately, then draw the calculated volume of each into the same syringe just before injection. This calculator works out those individual volumes for you.

For each peptide: volume = dose × BAC water ÷ vial strength. Add the per-peptide volumes together to get your total draw.

Example: a 5 mg peptide reconstituted with 2 mL BAC, dosed at 250 mcg, needs 0.10 mL. A second 10 mg peptide in another 2 mL vial dosed at 1 mg needs 0.20 mL. Total syringe draw: 0.30 mL = 30 units.

Draw the largest volume first to minimise plunger travel between vials. Insert the needle, withdraw, then move to the next vial without expelling. Air-prime once at the start; do not push air into each vial repeatedly.

A peptide is least soluble at its isoelectric point, the pH at which the molecule carries no overall charge. With no net charge left to make them repel each other, the molecules associate and come out of solution. Holding the pH away from that point in either direction keeps a peptide dissolved, though once it has already precipitated, correcting the pH will not reliably bring it back. The effect is predictable enough that laboratories use it deliberately to drop a protein out of solution on purpose.

This is why the liquid matters more than the peptides. Two peptides sitting in ordinary bacteriostatic water are usually close to neutral, and combining them changes the pH very little. Adding something strongly acidic can drag the mixture through that point and crash it.

Unbuffered NAD+ is the usual culprit. It reconstitutes strongly acidic, commonly cited at around pH 3 to 4. Drawn into a syringe alongside a peptide in bacteriostatic water it can precipitate the peptide on contact, normally visible straight away as cloudiness, wisps or fine specks. Buffered NAD+ ships with a stabiliser that brings it nearer to neutral, which is also commonly reported to sting less going in.

The same caution applies to anything supplied with an acidic diluent, dilute acetic acid being the most common. Keep those in a syringe of their own.

Cloudiness, wisps or visible specks after combining mean something has come out of solution. Warming, rolling or shaking will not bring it back, and you can no longer tell how much of the dose is still dissolved. Do not inject it.

Clear is not proof that a combination worked, though. Precipitation is the failure you can see; a change in pH can also affect how stable a compound is over the hours that follow, and that gives you nothing to look at.

There is no published compatibility table for these compounds. Hospital pharmacies work from tested compatibility data for intravenous medicines, and no equivalent exists for research peptides, so any list presented as definitively safe to combine is going beyond the available evidence. Your prescriber or compounding pharmacist is the right person to confirm a specific combination.

If you are unsure, use two syringes. Injecting separately in the same session, at different sites, removes the question entirely and costs one extra syringe.

The practical sub-cutaneous tolerance for a single injection site is around 1 mL. Above that, split between sites or thin the blend by using a higher BAC volume per vial. The calculator will warn you if your total draw exceeds your chosen syringe.