The short answer
- A weekly GLP-1 log needs the date and time, the medicine and prescribed dose, the injection site, and any side effects. Weight and notes such as the pen's lot number are useful extras.
- Paper is free and private but can't remind you of anything. Spreadsheets are flexible and easy to share but entirely manual.
- Notes plus Reminders on iPhone is quick to set up but has no structure or charts.
- A dedicated tracker app adds dose reminders, a built-in site rotation and progress charts. You give up some flexibility for that.
- If you forget doses, use something that reminds you. If you mainly need a record for appointments, any method you keep up with is fine.
Once you start a weekly injection such as Mounjaro, Wegovy, Zepbound or Ozempic, it quickly becomes hard to answer questions from memory. When did I last inject? Which side did I use? Was the nausea worse after the dose went up? A simple injection log answers all of them.
There are four common ways to keep that log: a paper diary, a spreadsheet, the Notes and Reminders apps already on your phone, or a dedicated tracker app. We make JabKeeper, one of those apps, so we have an obvious interest here. This guide still sets out honestly where each method works and where it doesn't, so you can pick the one you'll actually keep up with.
What a good injection log records
Whichever method you use, the useful information is the same. The details matter more than they first appear. Medicine leaflets give missed-dose rules in days since the missed injection: the Mounjaro label allows a late dose within four days, for example. A log with an exact date and time lets you check that instead of guessing.
| Field | Example | Why it helps |
|---|---|---|
| Date and time | Sunday 14 Sept, 8:15pm | Shows when the next dose is due and how late a missed dose is. |
| Medicine and dose | Mounjaro 5 mg | Keeps an accurate history of every dose step your prescriber gave you. |
| Injection site | Abdomen, left | Makes it easy to use a different spot each week, as the leaflets ask. |
| Side effects | Nausea, 2 out of 5, day 2 | Turns a vague memory into a pattern you can discuss at an appointment. |
| Weight | 84.2 kg | Lets you see a trend rather than reacting to one weigh-in. |
| Notes | New pen, lot D12345 | Useful if a batch is ever recalled or you need to report a problem. |
The four methods side by side
The table below compares the methods on what matters for a weekly routine. "Manual" means the method can do it, but only if you set it up and keep it up yourself.
| Paper diary | Spreadsheet | Notes + Reminders | JabKeeper | |
|---|---|---|---|---|
| Cost | A notebook | Free (Sheets, Numbers, Excel) | Free, built into iPhone | Free for two dose records, $9.99 once for everything |
| Dose reminders | No | No | Repeating reminder | Day before and on the day |
| Next injection site | Manual | Manual or formula | Manual | Shown automatically |
| Weight chart | No | If you build one | No | Yes, with goal date estimate |
| Side-effect history | Free text | Columns you design | Free text | Symptom and 1–5 severity |
| Sharing with a clinician | Bring the notebook | Export or print | Share a note | Show the screen; no export yet |
| Where data lives | On paper | Your device or a cloud account | iCloud if enabled | Only on your iPhone |
| Survives losing your phone | Yes | If stored in the cloud | If iCloud is on | No backup or sync |
A paper diary
A notebook in the kitchen drawer is the lowest-tech option, and it works well for some people. It costs almost nothing, never needs charging and shares no data with anyone. Some clinics also hand out printed diary sheets, which keeps things consistent with what your nurse expects to see.
The weaknesses show up over months. Paper can't remind you that tomorrow is injection day. It won't notice that you've used your left thigh three weeks running, and it can't draw a weight trend. It's also easy to leave at home on the day you need it. If you choose paper, rule your columns in advance so each week's entry takes the same shape. Pair it with a separate phone reminder.
A spreadsheet
Spreadsheets suit people who like control. You decide the columns, you can chart weight over time, and exporting a PDF for an appointment takes seconds. A simple layout looks like this:
| Date | Time | Medicine | Dose (mg) | Site | Weight | Side effects (0–5) | Notes |
|---|---|---|---|---|---|---|---|
| 07/09/2026 | 20:00 | Wegovy | 0.5 | Thigh R | 91.0 kg | Nausea 1 | — |
| 14/09/2026 | 20:10 | Wegovy | 0.5 | Abdomen L | 90.4 kg | None | New pen |
The trade-off is that nothing happens unless you do it. You have to open the file, remember which site comes next and build any charts yourself. Typing into a spreadsheet on a phone is fiddly, which is often why entries stop after a few weeks. Think about where the file lives, too. A spreadsheet in a cloud account is backed up, but your health information then sits with that provider under your account.
Notes and Reminders on iPhone
If you want something today without installing anything, the built-in apps go a long way. In Reminders, create a reminder for your injection time and set it to repeat weekly. In Notes, keep a running list with one line per dose. It's quick, free and, with iCloud turned on, it survives a lost phone.
What you don't get is structure. Notes won't total anything, chart your weight or tell you which site is next. Scrolling back through months of free text before an appointment is slow. Apple's Health app has a Medications feature that sits between Notes and a dedicated app. We compare it in detail in Apple Health Medications vs JabKeeper.
A dedicated tracker app
Tracker apps are built around the weekly rhythm, so the routine takes care of itself. In JabKeeper, you pick your medicine and prescribed dose once, along with your injection day and time. After that, logging a dose is a few taps: the dose is pre-filled, the next site in your rotation is selected, and the date and time default to now. Reminders arrive the day before and at injection time. With the lifetime unlock, weight, goal progress, side effects and food all sit in the same diary.
There are honest limits. JabKeeper handles one weekly injection at a time, not daily medicines. It runs on iPhone only, and it doesn't yet export to a spreadsheet or PDF. It also keeps the diary only on your iPhone, with no account, cloud sync or backup. That protects your privacy, but it means a lost phone takes the diary with it. If you want that trade-off explained further, read our guide to GLP-1 tracker privacy. Other apps make different choices: see Shotsy vs JabKeeper for a cloud-synced alternative.
Try JabKeeper free
Doses, reminders, injection sites, weight and side effects in one private iPhone diary. No account, and $9.99 once to unlock everything.
Which method should you choose?
The best injection log is the one you still fill in six months from now. Match the method to the problem you're actually trying to solve:
Choose paper if
- You rarely forget doses and just want a record
- You'd rather keep health details off your phone
- Your clinic already gives you diary sheets
Choose a spreadsheet if
- You want custom columns and your own charts
- You regularly send records to a clinician
- You log mostly from a computer
Choose a tracker app if
- You want reminders and your next site shown every week
- You'd like weight and side effects in the same place
- Logging needs to take seconds, not minutes
You can also combine methods. Plenty of people use an app for the weekly routine and keep a short paper note of dose changes for appointments. If Mounjaro is your medicine, our Mounjaro tracker guide walks through a complete weekly setup. Whatever you choose, pair it with a sensible injection site rotation.
Frequently asked questions
What should I record in a GLP-1 injection log?
The date and time, the medicine and prescribed dose, the injection site and any side effects. Weight and notes such as the pen lot number are useful extras.
Do I need to log the time of my injection?
It helps. Missed-dose rules in medicine leaflets are counted in days since the missed injection, so an exact date and time makes it easier to follow your leaflet and answer your prescriber.
Can I use a spreadsheet and an app together?
Yes. Some people use an app for weekly reminders and site rotation, and keep a short spreadsheet or paper note of dose changes to bring to appointments.
Can JabKeeper export to a spreadsheet?
Not at the moment. Your JabKeeper diary stays on your iPhone, and you can show your dose history at an appointment.