Tirzepatide Tracker App
A tirzepatide tracker keeps a once-weekly injection routine readable months later: the day and time, the site, the pen or compounded vial it came from, what changed and when, and the weight trend alongside. Pepti keeps that record on your iPhone with no account. It records the figure you already have; it never tells you what dose to take.
By Tessaro Pty Ltd, the maker of Pepti · Reviewed
This page covers tracking tirzepatide in an app — the one-time setup, the weekly entry, keeping a single record through changes, supply and cost, and reading the week. The compound itself, including its trials, its half-life and why we publish no dosing, is covered on the tirzepatide reference page, whose sources this page links below. It is written by the maker of Pepti, so read the Pepti-specific parts as a description of our own app.
Get Pepti on the App StoreWhat shapes a tirzepatide record
Tirzepatide is a dual agonist at the GIP and GLP-1 receptors, given as a once-weekly subcutaneous injection according to its US label. Two things shape a good record of it: entries are few, so each has to stand on its own, and things change over time. A routine that runs for months will see changes — a new pen, a move between pens and compounded vials, a new figure, a different injection day — and a tirzepatide log is only as useful as its record of them. Logging one injection is easy; keeping one honest record through every change is what a tracker is really for.
Setting up the schedule
You add tirzepatide, set the schedule to weekly, and pick the weekday and time you inject; Pepti reminds you then, showing your own figure in your own unit. The schedule carries a start date and can be given an end date, so the history of what you were on, and from when, stays intact. If your injection day moves, change it in the schedule and note it on the next entry; the reminder follows the new day.
The weekly entry
- The time, not just the day — drift from Monday morning to Tuesday night only shows in the record.
- The figure you were given — in the unit you think in. Pepti records it; it never calculates or suggests one.
- Pen or vial, and which one — so a new pen or a newly mixed vial starts a clean line in the supply records.
- Injection site — chosen with the record of where recent injections went.
- Notes and side effects — a line of text or a side-effect entry; Pepti stores them without interpreting them.
- Weight — on whichever day you weigh, logged the same way each time and placed on the same timeline.
Keeping one record through changes
What makes a long tirzepatide history readable is the dates of change. Each of these deserves a note on the day it happens.
| Event | What to record | Why it matters later |
|---|---|---|
| New pen started | The date, and the strength from the label | Separates one pen’s entries from the next |
| New vial mixed | The date, the water added and the resulting concentration | Concentration varies between compounded preparations |
| Supply form switched | The date, and pen or vial from then on | Unlabelled entries are ambiguous later |
| Figure changed | The date it changed | Turns a list of entries into a readable history |
| Week missed or moved | That it happened, and the new day | A recorded gap can be read; a hidden one cannot |
| Compound switched | The end of one schedule and the start of the next | Keeps both periods on one timeline |
The last row matters if you move between weekly compounds: in Pepti the earlier schedule ends and the new one starts on the same timeline, with the weight trend running through both. The one direct trial comparing tirzepatide with semaglutide for weight management in people without diabetes reported group averages (Aronne et al., NEJM 2025, covered on our reference page, which also covers the earlier head-to-head trial in type 2 diabetes); your own before-and-after line is a record of one person, not a comparison of compounds.
Rotation that survives a supply change
Site rotation is the one part of the record that should not reset when anything else changes. Pepti’s twelve sites — abdomen, thigh, deltoid, glute, love handle and tricep, each left and right — are tracked against your logged injections rather than against a particular pen or vial, so a new pen or a supply switch never resets it. When you log, the app suggests a site you have not used recently, on the opposite side from the last one, and its site view shows which areas have been favoured. The rotation guide explains the scheme.
Supply records and cost
Enter what a pen or vial holds, its lot and the expiry printed on it, and Pepti links every entry to it and warns as the expiry you entered approaches; for a compounded vial it also records the date you mixed it. It does not work out doses remaining or a run-out date.
You can add the price too, kept with the pen or vial; the app does not divide it into a cost per injection. The figures are yours; the app only records them.
Reading weight against the week
If weight is what you are watching, the injection timeline gives it context. Pepti plots weigh-ins on the same timeline as the weekly entries, so you can see a trend across months and check whether a flat stretch lines up with missed weeks, a supply change or a new figure — things a separate weight app cannot show you. Take readings the same way each time; single weigh-ins vary from day to day. The chart shows what you recorded and forecasts nothing.
Half-life, and why the dated log matters
The US label reports an elimination half-life of approximately five days for tirzepatide (FDA label, section 12.3), the value our tirzepatide page cites. With a five-day half-life and seven days between injections, successive injections still overlap, though less than at a seven-day half-life. The app does not chart levels; in Pepti a moved or missed week shows in the dated log itself. The free half-life decay calculator on this site draws a reference curve from a value you enter; it depicts timing, does not measure levels in your body and does not predict response.
Privacy: on your iPhone, no account
Pepti keeps a tirzepatide record where it is made: on your phone. There is no account to create, and the injection log, supply records, notes and weight trend stay on the device. There is no cloud sync. That data leaves your phone only if you turn on the AI coach or lab-report import, both behind one consent switch, and then only your coach messages with the app context they need, or the report you import, are sent to Pepti’s server and processed by Anthropic. With both off, there is no server copy of your routine for anyone to lose, sell or hand over.
Is Pepti the right tirzepatide tracker for you?
If you inject compounded tirzepatide from vials on an iPhone, Pepti is built for you: the vial records, the link from each injection to its vial and the change history are its core. If you only use prefilled pens, it logs them properly, but a pen-first app may be simpler; Pepti vs Shotsy sets out that trade-off. Pepti needs iOS 17.2 or later and has no Android version; pricing is in the questions below. Our tracker comparison covers the rest of the field with dated sources, and the semaglutide tracker and GLP-1 tracker pages cover the other weekly compounds.
Sources (2)
- Tirzepatide — the US FDA label (section 12.3) states an elimination half-life of approximately 5 days. FDA label (DailyMed)
- Aronne et al., New England Journal of Medicine, 2025 — head-to-head comparison of tirzepatide and semaglutide (SURMOUNT-5), cited on our reference page. PubMed 40353578
Common questions
What is a tirzepatide tracker app?
A tirzepatide tracker app is a record-keeping tool for a once-weekly injection routine. It stores the day and time of each injection, the site, the pen or compounded vial it came from, and what changed and when. Pepti adds each pen or vial's lot, reconstitution and expiry dates. It never decides anything medical for you.
Can I track compounded tirzepatide from vials?
Yes, that is what Pepti is built around. You record the peptide in the vial, the water you added, the lot and the date you mixed it, and each injection you log is linked to that vial. Each vial is set up on its own, because concentration varies between compounded preparations. Pepti does not calculate concentrations, draw volumes or syringe units; the free reconstitution calculator on this site does that arithmetic.
Can I keep one record if I switch from semaglutide to tirzepatide?
Yes. End the earlier schedule and start the new one, and both periods stay on the same timeline with the weight trend running through them. The date of the switch is the most useful entry in the record. A personal before-and-after line is a record of one person, not a comparison of the two compounds.
What is tirzepatide's half-life?
The US FDA label reports an elimination half-life of approximately five days. Pepti does not chart levels; the free half-life decay calculator on this site draws a reference curve from a value you enter. The curve shows timing only, not levels in your body or a prediction of response.
Does Pepti tell me what tirzepatide dose to take?
No, nowhere, by design. You enter the figure you were given by whoever directs your use, and Pepti records it with the date, time, injection site and vial. It never suggests, recommends or changes that figure, and this page contains none.
Is my tirzepatide data private?
There is no account and no sign-up, and your log, supply records, notes and weight trend stay on your iPhone. There is no cloud sync. That data leaves your phone only if you turn on the AI coach or lab-report import, both behind one consent switch, and then only your coach messages with the app context they need, or the report you import, are sent to Pepti's server and processed by Anthropic.
How much does Pepti cost?
Pepti is $12.99 per month or $49.99 per year in USD, with no free trial; you can cancel anytime. There is one tier and no free version: every feature is included, with nothing gated behind an upgrade, and there are no ads in the app. Your protocol and health logs are not used for advertising; install attribution uses Apple's tracking permission prompt.
How long can tirzepatide stay out of the fridge?
The US label for tirzepatide injection says single-dose pens and single-dose vials can be stored unrefrigerated, at temperatures not exceeding 30°C (86°F), for up to a total of 21 days, and should be kept in the original carton to protect them from light. Other presentations have their own limits on the label, and compounded material follows the pharmacy's instruction. Log each time it leaves the fridge, because the allowance is a total.
Can an app tell me my exact tirzepatide level?
No. An app cannot measure what is in your body, and Pepti does not chart medication levels. The free half-life decay calculator on this site plots a curve from a half-life you enter, which shows timing only. It is not a measurement of your level and not a prediction of how you will respond.
If you inject tirzepatide weekly on an iPhone and want one private record that holds through every change of pen, vial and schedule, Pepti is built for that. If you are on Android, or a pen-only routine suits a lighter tool, the comparison pages above will point you somewhere better.
Get Pepti on the App StoreThis page describes record-keeping. It does not recommend tirzepatide or any other substance, and it provides no dose figure and no schedule. Approved-product dosing is a matter for the product label and for whoever directs your use.
Not medical advice. Pepti is a record-keeping tool, not a medical device.
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