How to track peptide doses
The short version: record each vial once (milligrams, water, mix date, concentration), work out the syringe units for your dose from that, then log every injection at the moment you give it with the compound, dose, units, site and time. Review the log once a week. Anything less than that is where dosing mistakes come from; anything more is optional.
What to record
A log is only useful if it can answer three questions later: what did I take, how much, and when. For injectable peptides that means six fields per dose.
- Compound. The name as it appears on your vial. If you run two at once, log them as two entries, not one.
- Dose. In milligrams or micrograms, the amount you intended to take.
- Units. The number you drew on the syringe. This is not the same as the dose, and confusing the two is the single most common logging error.
- Vial. Which vial it came from. Two vials of the same compound mixed with different water volumes give different units for the same dose.
- Site. Where you injected, precisely enough to avoid it next time. Rotation guide →
- Time. Date and time, because half-life and spacing are measured from it. Half-life reference →
Optional but worth it over a few weeks: a one-line note on how you felt, your weight if that is a goal, and whether the injection stung or bruised. Patterns in those notes are what a weekly review is for.
Set up the vial once
The maths lives with the vial, not with the dose. Concentration is milligrams in the vial divided by millilitres of bacteriostatic water added. A 5 mg vial with 2 mL of water is 2.5 mg/mL. From there, a 250 mcg dose is 0.1 mL, which is 10 units on a U-100 insulin syringe. Work that out once, write it on the vial with the mix date, and every later dose is a lookup instead of a calculation. The calculator does the three steps and checks the dose fits your syringe →
If you use a U-40 syringe or one marked only in millilitres, the unit number is different for the same volume. Write down which syringe you used with the vial. How to reconstitute without damaging the vial →
Logging each dose
Log at the moment of the injection. A log reconstructed on Sunday from memory is mostly fiction about times and sites, and those are the two fields you will need when something feels off. If you use reminders, let the reminder be the thing you tap to log, so the record and the schedule are the same object.
Missed doses go in the log too. A gap you can see is information; a gap you hid from yourself is not. For weekly GLP-1 medications the labels define how late is too late. The missed-dose rules →
The weekly review
Once a week, look at four things: whether you took what you planned, whether times drifted, which sites you used, and how much of each vial is left. Vial tracking is the one people skip and then regret: a vial mixed with bacteriostatic water is commonly labelled for 28 days after first puncture, so the mix date decides when it is done regardless of how much is left. Why the 28-day convention exists →
Share the review with whoever is supervising the protocol. A dated log with sites and doses is more useful to a clinician than a description from memory, which is why Bo's export builds one as a PDF.
Spreadsheet or app
A spreadsheet is fine for one compound and one vial. It starts to fail at two vials of the same compound with different concentrations, because the sheet does not know which vial a row came from unless you type it every time, and at two compounds with different schedules, because the sheet cannot remind you. The two errors it invites are typing units where the dose should go, and carrying a units number from an old vial to a new one mixed with a different volume.
An app fixes this by storing the vial and deriving the units. It should also do the site map, the reminder and the export. What the current apps advertise, compared honestly →
Bo does the vial maths for you
Add the vial once, drag the syringe to log, tap the site on the body map. Estimated levels, reminders and the doctor PDF come with it.
Educational information only. Bo is a tracking app, not a medical device, and nothing here is medical advice, a dosing recommendation, or a substitute for your prescriber. Half-lives are population averages from the sources cited on each row; individual clearance varies with body weight, kidney and liver function, and other medication.