Six fields, thirty seconds per dose. What to write down after an injection, why the site column earns its keep, and where to keep it.
Key points
- 01Six fields is the whole job. Date, time, medication and strength, dose, site, and anything that felt unusual. That is thirty seconds of writing per dose, and it is the difference between remembering your routine and reconstructing it. Anything longer than six fields gets abandoned by week three.
- 02The site column is the one that pays. Rotation only exists if it is recorded. Published technique guidance ties repeated injection into the same area to hardened tissue and unpredictable absorption, and a written site column is the only practical way to see the pattern of the last ten doses rather than guessing at it.
- 03Lot number and expiry, once per device. Write the lot number and expiry from the carton when you start a new pen or vial. It costs one line, and it is the first thing a pharmacy or a manufacturer complaint line asks for if a device fails or a batch is recalled. Our post on returning a defective pen covers what those calls involve.
- 04Symptoms beside sites, not on a separate page. A lump that returns on one site, a sting that only happens in the thigh, a bruise every time on the left: none of that is visible in memory and all of it is obvious in a column. Keeping the note next to the site is what turns a vague sense that something is off into something a clinician can act on.
- 05It answers the question that causes double doses. Did I actually inject on Sunday? A weekly medication and a busy week is all it takes for that doubt to appear, and our post on an accidental double dose exists because of how people resolve it. A line on paper answers it in one second, without a decision.
- 06The format matters far less than the location. A card taped inside a cupboard door, a notes app, a calendar entry or the carton itself all work. What matters is that it lives where you inject, so the entry happens while the needle is still in your hand rather than as a thing to do later.
Frequently asked questions
What should I write down after each injection?+
Date, time, medication and strength, dose, site, and anything unusual. Add the lot number and expiry once per new device. Educational information only, not medical advice.
Do I need an app for this?+
No. Paper kept where you inject beats an app you have to unlock and find. Use an app if you already live in one, since the best record is the one that actually gets filled in.
Why record the lot number?+
Because a pharmacy or a manufacturer complaint line will ask for it if a device fails or a batch is recalled, and it is printed on a carton that is usually already in the bin by then.
How long should I keep the record?+
Long enough to show a pattern and to bring to appointments, which for most people means the current year. Site patterns and recurring reactions are the parts worth carrying forward.