The arithmetic behind a reconstituted peptide vial is short. The mistakes are not subtle, but they are common, and they are almost always off by a factor of ten.
Two formulas cover almost everything:
concentration (mg/mL) = vial mass (mg) / diluent volume (mL)
units on a U-100 syringe = (target dose in mg / concentration) x 100A U-100 insulin syringe is marked so that 100 units equals 1 mL. That single fact is where most of the confusion enters: the units printed on the barrel are a volume marking, not a dose.
A 5 mg vial reconstituted with 1 mL of bacteriostatic water:
The same 5 mg vial reconstituted with 2 mL:
Same vial, same syringe mark, half the dose. That is the whole reason the diluent volume has to live in the log entry rather than in your memory. If you would rather not redo this by hand each time you mix a vial, this peptide reconstitution calculator takes vial mass, diluent volume and target dose and returns the syringe marking, showing the intermediate concentration so you can sanity-check it against your own arithmetic.
Mixing mg and mcg. A dose written as "250" is 0.25 mg or 250 mcg depending on who wrote it, and the two are not the same number.
Assuming someone else's reconstitution. A conversion table copied from a forum post is only valid for the vial size and diluent volume that person used, which is frequently not stated anywhere in the post.
Reusing an old note after changing dilution. The most common failure, and the reason to write the reconstitution on the vial in marker the day you mix it.
Titration is a schedule, not a number. Escalation is conditional: hold at a dose until side effects settle, then step up. A flat list of past rows answers none of the questions you actually have, which are which step am I on, how long have I been here, and what is next. Recording the schedule alongside the doses is what makes a log answerable rather than merely complete.
Missed doses matter more than people expect. Missing by a day is usually uneventful. The trouble starts at three or four days, when the question becomes whether to take the dose now or skip to the next scheduled one, and that is exactly the moment a log of bare numbers offers no help. Write down what you did and why. Future you will not reconstruct the reasoning.
Travel breaks two things: the timing and the cold chain. Both are worth an explicit note rather than a silent mental adjustment, because timezone shifts make "same time each week" ambiguous, and an entry that says "delayed 6h, travel" is far more useful six months later than a quietly shifted timestamp.
The single most useful rule is one record, not a spreadsheet plus a notes app plus a calendar. Split records diverge, and the moment they disagree you have no way to tell which one was right.
I keep mine in the Peptide Tracker and Calculator for that reason: dose, schedule and reconstitution live in the same object instead of three places that drift apart. Its glossary of peptide terms is also a reasonable place to check terminology before assuming a forum post is using a word the way you are.