# GLP-1 guides for people actually on treatment.

Half-lives, dose ladders, pen click charts, injection sites, side-effect timing and food noise. Everything we had to work out to build Penwise, written down plainly, with the numbers shown rather than asserted.

## By medication

What tracking looks like on each product, including the pen, the dose ladder and the things that catch people out.

- [The Mounjaro tracker app that keeps your log on your phone](https://penwiseapp.com/en/guides/mounjaro-tracker): How to track Mounjaro (tirzepatide) properly: doses, the KwikPen, injection sites, side effects and where you actually are between shots.
- [The Ozempic tracker that knows which pen you are holding](https://penwiseapp.com/en/guides/ozempic-tracker): Tracking Ozempic (semaglutide) properly: four different pens, why the same dose is a different number of clicks on each, and where you are between shots.
- [A Wegovy tracker built around the sixteen-week climb](https://penwiseapp.com/en/guides/wegovy-tracker): Tracking Wegovy (semaglutide) for weight management: the five-step titration, both pen designs, and reading the weight trend against the dose you were actually on.
- [A Zepbound tracker for the whole tirzepatide ladder](https://penwiseapp.com/en/guides/zepbound-tracker): Tracking Zepbound (tirzepatide) for weight management: six strengths, two pen designs, the thirty-day clock, and reading weight against the dose you were on.
- [A Saxenda and Victoza tracker built for a daily injection](https://penwiseapp.com/en/guides/saxenda-tracker): Liraglutide is daily, not weekly, and a thirteen-hour half-life changes everything about reminders, site rotation and what a missed dose means.
- [Tracking Rybelsus and the other oral semaglutide tablets](https://penwiseapp.com/en/guides/rybelsus-tracker): Oral semaglutide has no site, no pain and no clicks – but a strict fasting window, a daily cadence and three different dose ladders that are not interchangeable.

## Understanding your treatment

How long the medication lasts, how the two main drugs differ, when side effects tend to land, and what food noise really is.

- [Mounjaro vs Ozempic: what actually differs](https://penwiseapp.com/en/guides/mounjaro-vs-ozempic): Two receptors versus one, five days of half-life versus seven, six fixed strengths versus a dial. A comparison of the things that change your week.
- [Mounjaro vs Wegovy: two weekly injections, two different drugs](https://penwiseapp.com/en/guides/mounjaro-vs-wegovy): Both are weekly, both are for weight, and they are not the same molecule. The head-to-head trial, the dose ladders, the pens and what actually changes for you week to week.
- [Zepbound vs Mounjaro: the same drug with two labels](https://penwiseapp.com/en/guides/zepbound-vs-mounjaro): Identical molecule, identical device, identical ladder. What actually differs is the licence on the box, and that turns out to matter for cost, supply and paperwork.
- [How long does Mounjaro stay in your system?](https://penwiseapp.com/en/guides/how-long-does-mounjaro-stay-in-your-system): Tirzepatide has a five-day half-life. Here is what that means week by week, why it takes a month to reach steady state, and where the trough you can feel comes from.
- [How long does Ozempic stay in your system?](https://penwiseapp.com/en/guides/how-long-does-ozempic-stay-in-your-system): Semaglutide has a seven-day half-life, so it clears over about five weeks and doubles on itself before it settles. What that means week by week.
- [The GLP-1 side effect timeline: what lands when](https://penwiseapp.com/en/guides/glp-1-side-effects-timeline): Nausea, fatigue, constipation and reflux do not arrive at random. Here is where they usually sit in the week, in the ladder and in the treatment.
- [What food noise is, and why GLP-1 medication turns it down](https://penwiseapp.com/en/guides/what-is-food-noise): The constant background chatter about food that most people never had a word for – what it is, why it goes quiet on a GLP-1, and why it comes back late in the week.
- [The GLP-1 weight loss plateau: what it is and what it is not](https://penwiseapp.com/en/guides/glp-1-weight-loss-plateau): Most reported plateaus are two weeks of noise on a trend that has not changed. Here is how to tell a real one from a scale reading, and what the log should show.
- [What happens when you stop a GLP-1 medication](https://penwiseapp.com/en/guides/what-happens-when-you-stop-a-glp-1): The drug leaves over weeks, not days, and appetite returns as the level falls. What the withdrawal trials actually found, and what to have written down before you stop.
- [GLP-1 weight loss timeline: what happens month by month](https://penwiseapp.com/en/guides/glp-1-weight-loss-timeline): Month one is titration, not results. What the trials actually recorded at each stage, why the first six weeks mislead everybody, and how to read your own curve.
- [Muscle loss on a GLP-1, and what to do about it](https://penwiseapp.com/en/guides/muscle-loss-on-glp-1): Every kilogram lost contains some lean mass. What proportion, why it matters more in year two than year one, and the two things that change the ratio.
- [Hair loss on a GLP-1: why it happens and when it stops](https://penwiseapp.com/en/guides/glp-1-hair-loss): It is almost always telogen effluvium from rapid weight loss rather than a direct drug effect. Why it starts months after the trigger, how long it runs, and what actually influences it.
- [Retatrutide: the triple agonist, and where it actually stands](https://penwiseapp.com/en/guides/retatrutide): Three receptors instead of two, the phase 2 numbers that got everyone talking, and the important part: it is investigational and not approved anywhere.
- [Ozempic face: what it is and what actually causes it](https://penwiseapp.com/en/guides/ozempic-face): Not a drug effect on the face. Fat loss reaches the face like everywhere else, and it shows more there because of how facial fat is built.
- [GLP-1 medications and mood: what the reviews found](https://penwiseapp.com/en/guides/glp-1-and-mood): Regulators reviewed the suicidality signal and did not find a causal link. What that does and does not settle, and the mood changes people genuinely report.

## Day to day

Clicks, sites, discard windows, missed doses and titration. The mechanical detail that decides whether a week goes smoothly.

- [GLP-1 medications and contraception: the interaction people miss](https://penwiseapp.com/en/guides/glp-1-and-contraception): Tirzepatide carries a specific label warning about the pill that semaglutide does not. When it applies, how long for, and what to do about it.
- [GLP-1 medications before surgery, endoscopy and anaesthesia](https://penwiseapp.com/en/guides/glp-1-before-surgery): A stomach that empties slowly is a real anaesthetic problem. Why holding doses is now standard guidance, how far ahead, and why nobody should stop on their own.
- [The GLP-1 pen click chart, and why one number never fits two pens](https://penwiseapp.com/en/guides/glp-1-pen-click-chart): What a click is actually worth on every Ozempic, Mounjaro, Wegovy, Saxenda and Victoza pen, and the one rule that makes all of it make sense.
- [How long does a GLP-1 pen last once you start it?](https://penwiseapp.com/en/guides/how-long-does-a-glp-1-pen-last): Every pen has two clocks: the doses left in it and the days it may still be used. The chart, and what happens when the second one wins.
- [GLP-1 injection sites, and rotation that actually rotates](https://penwiseapp.com/en/guides/glp-1-injection-sites): Abdomen, thigh or upper arm, and the question nobody can answer from memory: which one hurts least for you, and where did the last four shots go.
- [Missed a GLP-1 dose? What it actually costs you](https://penwiseapp.com/en/guides/missed-glp-1-dose): A day late on semaglutide is nothing. A day late on liraglutide is a real gap. Why the same question has a different answer for every product.
- [GLP-1 dose schedules: every ladder, and why the steps are four weeks](https://penwiseapp.com/en/guides/glp-1-dose-schedule): The titration ladder for every GLP-1 product side by side, and the pharmacology that decides how long each step has to last.
- [Storing a GLP-1 pen, and travelling with one](https://penwiseapp.com/en/guides/glp-1-pen-storage-and-travel): Fridge, room temperature, hand luggage and heat. The rules that hold for every pen, the ones that vary by product, and what to do when a pen has been somewhere it should not have been.
- [Choosing your injection day, and changing it safely](https://penwiseapp.com/en/guides/glp-1-injection-day): Which day you inject changes which days your side effects land on. The 72-hour rule for moving it, and why the day before your next shot is the one that feels different.
- [Nausea, constipation and sulphur burps: managing the gut effects](https://penwiseapp.com/en/guides/glp-1-nausea-and-constipation): Why these drugs upset the gut, what actually helps for each effect, the symptoms that mean call someone today, and when it is a dose question rather than a coping question.
- [Alcohol on a GLP-1: what changes and why](https://penwiseapp.com/en/guides/alcohol-on-glp-1): A lot of people find they simply want to drink less. Why that happens, what a slowed stomach does to how alcohol hits, and the situations that need real caution.

## Choosing a tracker

An honest look at the apps in this category, what they cost, and what happens to your medication history inside them.

- [A Shotsy alternative, and how to bring your history with you](https://penwiseapp.com/en/guides/shotsy-alternative): What Penwise does that Shotsy does not, what it costs instead, and the guided import that brings your shots, weights and side effects across.
- [How to choose a GLP-1 tracker app](https://penwiseapp.com/en/guides/best-glp-1-tracker-apps): Twelve questions worth asking before you put a year of medication history into an app, and what the honest answers look like.
- [Why a GLP-1 tracker should not have a server](https://penwiseapp.com/en/guides/private-glp-1-tracker): Your medication history is one of the most sensitive records you will ever create. Here is what a cloud tracker actually holds, and what an on-device one cannot.