Most people on a GLP-1 medication keep some kind of record, and most of those records turn out to be useless at the moment they are needed. A row of dates and milligrams tells you what you took. It does not tell you why week six felt different from week five, or whether the nausea you are trying to describe to a prescriber followed a dose change or a travel week. The difference is which fields you capture at the time of the injection, when the information is still free.
| Field | Why it earns its place |
|---|---|
| Date and time | Lets you see the real interval between doses, which drifts by a day or more over a few months and is the usual explanation for an unexpectedly rough week. |
| Dose in mg | Obvious, but record the actual delivered dose, not the pen label, if you are splitting or using a vial. |
| Injection site | Abdomen, thigh or upper arm, and which side. Rotation is the only way to notice a site that has become consistently sore. |
| Side effects, with a day offset | Nausea on day 1 and nausea on day 5 mean different things. Record when, not just whether. |
| Anything unusual that week | Illness, alcohol, a long flight, a skipped meal pattern. This is the field everyone omits and later wishes they had. |
If you are drawing from a vial rather than using a fixed-dose pen, the number you want in the log is milligrams delivered, and getting there means going through concentration and syringe units. A vial reconstituted to a given concentration turns a units marking on an insulin syringe into a dose only after you divide correctly, and doing that in your head at 6am is how people end up logging a number that never went into them. Work it out once per vial, write the units-to-milligrams conversion on the vial itself, and log the milligrams. A peptide dose calculator and tracker is worth using here purely because it keeps the reconstitution maths and the dose history in the same place, so the logged number and the number you actually drew cannot drift apart.
When a prescriber asks whether you are ready to step up, the useful answer is not "I feel fine". It is something like: at this dose for five weeks, nausea confined to days one and two for the first three weeks and absent since, no missed doses, interval held at seven days plus or minus one. That answer only exists if the log has intervals and day offsets in it. A log that has only dates and milligrams cannot produce it, and the conversation falls back to recollection.
None of this requires a particular tool. A paper notebook with those five columns beats a sophisticated app used inconsistently. What matters is that the fields are chosen before you need them, because the value of a dose log is entirely retrospective and you only get one chance to capture each entry.