A reviewable reconstitution entry captures the label values, the diluent, the resulting concentration, the target, the computed mL and units, the syringe scale, the date, and a storage note. Record every value as written, and mark unknowns instead of guessing.
A reconstitution log is only as useful as the entry you can defend weeks later. When you reopen a record, you are not asking "what number did I draw?" You are asking "can I reconstruct exactly how that number was reached, from the label to the syringe?" That is the difference between a note and an auditable entry: a note has the answer, an entry has the inputs that produce the answer. This guide lists the complete field set for one reconstitution entry and explains why each field earns its place. It is a documentation practice, not dosing guidance, and every figure below is an illustrative example of the arithmetic.
The complete field list
A single reconstitution entry should capture nine fields. Miss one and the entry usually becomes unverifiable, because the missing value is the one a later review needs most.
- Compound / vial label: the identifier you can tie back to a physical vial.
- Peptide amount from the label (mg): the starting quantity, copied exactly as printed.
- Diluent type: for example bacteriostatic water or sterile water.
- Diluent volume added (mL): how much liquid went in.
- Resulting concentration (mg/mL): computed, not guessed.
- Target amount: the amount used in the calculation, in mg or mcg.
- Computed volume (mL) and units: the draw the math produced.
- Syringe scale used: U-100 or U-40, stated explicitly.
- Reconstitution date: when the vial was mixed.
- Storage note: where and how the vial is kept.
The rest of this article walks each field and shows what breaks when it is absent.
Identity fields: label and peptide amount
The compound and vial label is the anchor. Without it, an entry floats free of any physical vial, and two vials on a shelf become indistinguishable in the record. Copy the label text as written, including the identifier or lot marking if there is one.
The peptide amount in mg is the number every downstream calculation depends on. Record it exactly as printed on the label, not as you remember it. If a label reads 5 mg, the entry says 5 mg. This is the single most consequential value in the log, because concentration is built directly from it.
Diluent fields: type and volume
The diluent type matters for review because it changes how the vial behaves over time. Bacteriostatic water contains roughly 0.9% benzyl alcohol as a preservative; sterile water for injection has none. A reviewer who sees only a volume, with no type, cannot judge how the storage note should be read. The details of that trade-off are covered in BAC water vs. sterile water.
The diluent volume is the other half of the concentration formula. It is also the field people most often approximate, and approximation here contaminates every number that follows. More diluent means a lower concentration and a larger draw for the same target amount; less diluent means the opposite. Record the volume you actually added, not the volume you intended to add.
The computed fields: concentration, volume, units
Concentration is the first computed value, and it follows one formula:
Concentration (mg/mL) = peptide amount (mg) ÷ diluent volume (mL)
Using the label values above, 5 mg dissolved in 2 mL gives 2.5 mg/mL. Recording the concentration alongside its two inputs lets a reviewer re-derive it and confirm nothing drifted.
The target amount then drives the draw volume:
Volume (mL) = target amount (mg) ÷ concentration (mg/mL)
An illustrative target of 0.25 mg (250 mcg) at 2.5 mg/mL gives 0.10 mL. Note the unit trap: targets are often written in micrograms while concentration is in mg/mL, and there are 1,000 mcg in 1 mg, so convert before dividing. Logging the target in the same units you calculated with prevents a silent factor-of-1000 error at review time. The full chain is broken down in peptide reconstitution math.
The syringe scale is not optional
A volume in milliliters still has to be read off a syringe, and the scale you used determines what the marks mean. On a U-100 syringe, 1 mL = 100 units, so units = mL × 100, and 0.10 mL is 10 units. On a U-40 syringe, 1 mL = 40 units. Recording the units without the scale is ambiguous: the same 0.10 mL is 10 units on one scale and 4 units on the other, and mixing U-100 and U-40 misreads by 2.5x. State the scale explicitly so the units in the entry are unambiguous. This is a common failure point, covered in reading units on an insulin syringe.
Date and storage note: the time dimension
The reconstitution date gives every other field a timeline. It tells a reviewer how old a mixed vial is and lets entries be ordered and compared. The storage note, for example "refrigerated" or a location, records the conditions the vial has been kept under since that date. Together they turn a static calculation into a record that ages meaningfully.
Record as written, mark unknowns
Two habits separate a trustworthy log from a tidy-looking one. First, record every value as written: copy the label, the volume you added, and the scale you used, not the ones you meant to use. Second, when a field is genuinely unknown, mark it unknown rather than filling in a plausible number. A guessed value is indistinguishable from a recorded one later, which makes the whole entry suspect. An entry that honestly shows a gap is more reviewable than one that hides it behind an invented figure.
Keeping the fields together
The reason these fields drift apart is that they are usually captured in different moments: the label when the vial arrives, the diluent when it is mixed, the math when a draw is prepared. PepSync's vial tracking keeps all nine fields in one entry, so the units on the syringe always trace back to the mg on the label, the concentration is computed rather than guessed, and the date and storage note stay attached to the values they describe. That is what makes an entry auditable: not the answer, but the complete, unedited chain behind it.
Frequently asked questions
What fields belong in a reconstitution log entry?
Capture the vial label, the peptide amount in mg from the label, the diluent type and volume, the resulting concentration in mg/mL, the target amount, the computed mL and units, the syringe scale used, the reconstitution date, and a storage note. Together these let you re-derive the draw from the label.
Why record the syringe scale in the log?
Because units are meaningless without it. The same 0.10 mL reads as 10 units on a U-100 syringe and 4 units on a U-40 syringe, so an entry that omits the scale is ambiguous and mixing the two misreads by 2.5x.
What should I do if I do not know one of the values?
Mark it as unknown rather than guessing. A guessed value looks identical to a recorded one at review time, so it undermines the whole entry, while an honest gap keeps the rest of the record trustworthy.