GLP-1 Side Effects Tracker: Log Every Symptom Next to Your Doses
Glapp is a free GLP-1 side effects tracker that puts every symptom on the same timeline as your doses, so you can finally see what each shot and dose step does to you. Log nausea, tiredness, constipation, headaches or any other side effect in a quick daily check-in and rate it low, medium or high. Glapp lines each rating up with your injection, your dose and your estimated medication level. Your weekly report shows the pattern, and a doctor's report turns weeks of check-ins into a record your prescriber can act on. It works with Zepbound, Mounjaro, Wegovy and Ozempic pens and with tirzepatide or semaglutide from a vial.
Start tracking your side effects free
Key numbers
| Number | What it means |
|---|---|
| Up to 44% | of people had nausea in weight-loss trials of GLP-1 medications, and most of it came while the dose was going up |
| 69,022 | users currently tracking GLP-1 side effects in Glapp |
| 4.8/5 | Glapp's rating on Trustpilot and the App Store, with 4.6/5 on Google Play |
Why track your GLP-1 side effects?
A side effect on its own doesn't tell you much. Nausea on a Tuesday means something different once you can see you took your shot on Sunday and moved up a dose last week. GLP-1 side effects follow your medication, and a side effects tracker is how you see that rhythm instead of guessing at it.
Side effects follow your shot
GLP-1 medications are weekly injections, so your medication level rises and falls across the week. Tirzepatide (Zepbound, Mounjaro) peaks about 24 hours after a shot, anywhere from 8 to 72 hours, and semaglutide (Wegovy, Ozempic) peaks one to three days after (Zepbound prescribing information; Wegovy prescribing information). Many people feel side effects most in those first days and much less by the end of the week.
Dose steps bring them back
Every GLP-1 starts low and goes up in steps, usually every four weeks. The prescribing information for both Zepbound and Wegovy says most nausea, vomiting and diarrhea happened while the dose was being increased. Logging through each step shows you which dose your body handled well and which one brought the hard weeks.
Patterns take weeks to show
One bad day is noise. Three weeks of check-ins show whether that bad day comes back on the same day after every shot, whether it's getting milder and whether it lines up with a dose change or a drop in hunger. Memory blurs those details within days.
Your prescriber needs specifics
"I felt sick sometimes" is hard to act on. "Medium nausea on the first two days after each shot, easing by week three at 7.5 mg" gives your prescriber something real to work with when deciding whether to hold a dose or move up.
How Glapp tracks your side effects
Daily side-effect check-ins
Pick any side effect, from nausea to fatigue to hair shedding, and rate it low, medium or high. One consistent rating a day is what makes trends visible later.
Every dose on the same timeline
Log each dose with its injection time, whether you use a pen or draw from a vial. Glapp's dosage calculator turns your vial's concentration into exact units, and vial tracking shows how much is left. Every check-in sits next to the dose you actually took.
Your estimated medication level
Glapp estimates your medication level through the day from your dose, your injection time and published half-life data: about 5 days for tirzepatide and about a week for semaglutide. Seeing your ratings rise and fall with that curve helps explain why some days are harder. It's an estimate for context, not a blood test.
A side-effects chart in Progress
The Progress tab charts your daily ratings over any period you choose, so you can tell a one-off rough day from a trend and watch each side effect fade.
Weekly progress reports
Every week Glapp brings your doses, check-ins, weight and hunger together in one report, with dedicated sections for your side effects and how they've changed.
A doctor's report you can share
Create a doctor's report, choose what goes in it and share it before or during your appointment. Your prescriber sees your symptom history next to your doses and progress.
Glapp does not provide medical advice or treat side effects. It shows your daily check-ins against your estimated medication levels so you have structured data to share with your prescriber.
What people say about tracking side effects in Glapp
Helps me predict hunger and side effects
“Life-changing app for Mounjaro people! Used Glapp since last year and can't imagine my journey without it. Love tracking shots, weight, side effects, and hunger all in one place. The "Shot Phases" feature shows medication levels rise and fall—so helpful for predicting hunger and side effects. Clear insights, progress reports, and personalized tips make it feel like a coach in my pocket. Takes the guesswork out of GLP-1 management. Absolutely essential!”
Shows me which side effects happen when
“The best app I have found for registering all my Mounjaro shots, getting weekly reports that study which side effect i get when and how to avoid it. I really enjoy the Wisdom function, that it searches through peer reviewed journals and also online communities to answer my question. I also enjoy being able to see weightloss and side effects by injection site.”
Helped when my side effects were tough
“The side effects the last few months have been tough. The comprehensive options to track these and provide some insight and tips has been so helpful! Love all the options for tracking and the handy infographics showing the cycle of the dose.”
Helps me talk to my physician about side effects
“This is a great app to have when on your GLP1 journey. It has helped me to recognize side effects and my progress. It is very beneficial when speaking with my Physician about side effects, weight loss progress, and general use of medication.”
Which GLP-1 side effects are most common?
For most people they're stomach-related and temporary. Here's what the weight-loss trials behind each prescribing information found at the highest dose, with placebo in brackets:
| Side effect | Tirzepatide 15 mg (Zepbound, Mounjaro) | Semaglutide 2.4 mg (Wegovy) |
|---|---|---|
| Nausea | 28% (8%) | 44% (16%) |
| Diarrhea | 23% (8%) | 30% (16%) |
| Vomiting | 13% (2%) | 24% (6%) |
| Constipation | 11% (5%) | 24% (11%) |
| Fatigue | 7% (3%) | 11% (5%) |
| Stopped because of side effects | 6.7% (3.4%) | 6.8% (3.2%) |
Sources: Zepbound prescribing information, Table 1; Wegovy prescribing information, Table 3.
These come from separate trials, so compare the pattern rather than the exact numbers. In both, more than 9 in 10 people stayed on treatment. For the full list, how long each side effect lasts and guides for each medication, see GLP-1 side effects.
A tracker helps with everyday side effects, but some need a call rather than a log. Contact your prescriber promptly if you can't keep fluids down, have severe or lasting stomach pain, pain in your upper right abdomen or yellowing skin or eyes. Swelling of your face or throat or trouble breathing needs emergency care.
What to log for each side effect
| What to log | Why it helps | How Glapp does it |
|---|---|---|
| The side effect and how strong it is | Mild queasiness and a day in bed need different conversations | Daily check-in with a low, medium or high rating |
| The day it happened | Shows where it falls in your shot cycle | Every check-in is dated and shown against your last injection |
| Your dose and injection time | Ties the side effect to what you actually took | Dose log for pens and vials, with a dosage calculator for units |
| Your dose step | Dose increases are the most common trigger | Your dose history shows when each step started |
| Your estimated medication level | Explains why the same dose feels different across the week | Estimated level chart built from your doses |
| Hunger and weight | Shows whether side effects move with appetite and progress | Hunger and weight sit in the same weekly report |
Glapp tracks and organizes your data; it never diagnoses. Severe or lasting side effects belong with your care team.
Track your GLP-1 side effects with Glapp and stay in control: your 30-day plan
Starting a GLP-1 or moving up a dose is when a side effects tracker earns its place. Log how you feel each day next to your doses, and you're in control. You'll know which day after your shot each side effect peaks, which step brought it on and whether it's easing, and you'll walk into your next appointment with facts instead of guesses.
Why Glapp? It's a top-rated GLP-1 tracking app used by 100,000+ people, rated 4.8/5 on Trustpilot and the App Store, and 4.6/5 on Google Play. Glapp grew out of Reddit GLP-1 support groups and is built by people who take GLP-1 medications themselves, so most features come straight from community requests. It works the way you take your medication: Zepbound, Mounjaro, Wegovy or Ozempic pens, or tirzepatide and semaglutide from a vial. It's grounded in published clinical trial data and peer-reviewed research, core tracking is free, and it syncs across iPhone, Android and web. Here's how to use it over your first 30 days.
Day 1: Start tracking your side effects
Use Glapp's daily check-in to record any side effect you notice and rate how strong it feels. Log your dose and injection time too, so everything that follows is based on what you actually took.
Day 3: Compare symptoms with your estimated medication level
Glapp estimates your medication level throughout the day from your dose and injection time. Seeing your ratings next to that estimate shows where each side effect falls in your shot cycle. The level is an estimate, not a blood test, and a matching pattern doesn't prove what caused a symptom.
Day 7: See how your side effects change
Open the side-effects chart in the Progress tab and pick the period to review. Your daily ratings appear on a timeline, so you can see whether a difficult day was a one-off or part of a trend.
Day 14: Look for patterns in your weekly report
Your weekly progress report brings your logged data together. Do side effects return on the same day after each shot? Did they start after a dose step? Do they move with your hunger? Two weeks of entries make these patterns easy to spot and give you specific questions for your doctor.
Day 30: Bring a clear record to your doctor
After a month, look at the bigger picture: are your side effects less frequent, the same or worse? GLP-1 medications reach a steady level after about four to five weeks at the same dose, so this is a good moment to review. Create a doctor's report, choose what to include and share it for a focused conversation about your next dose step.
Start tracking your side effects free
Frequently asked questions
What is the best app to track GLP-1 side effects?
The best one puts your side effects next to your doses, because that's where the pattern lives. Glapp was built for exactly that: daily check-ins with severity ratings, an estimated medication level, weekly reports and a doctor's report, for pens and vials alike. Core tracking is free on iPhone, Android and web.
Which side effects should I track?
Any you notice. Start with the common ones (nausea, diarrhea, constipation, vomiting, fatigue, heartburn and headaches) and add anything new, even if it seems unrelated. A side effect you log early is one you can trace later.
Is Glapp's side effects tracker free?
Yes. Core tracking, including daily side-effect check-ins and dose logging, is free.
Can I share my side effects with my doctor?
Yes. Create a doctor's report in Glapp, choose what to include and share it. Your prescriber sees your symptom history alongside your doses and progress.
Does Glapp work with my GLP-1 medication?
Yes. It works with Zepbound, Mounjaro, Wegovy and Ozempic pens and with compounded or generic tirzepatide and semaglutide from a vial. For vials, the dosage calculator converts your concentration into exact units.
Why do my side effects change through the week?
Because your medication level does. It peaks a day or a few days after each weekly shot and drifts down until the next one, so many people feel side effects most early in the week after their shot. Glapp shows your ratings against your estimated level so you can see your own rhythm.
Do GLP-1 side effects get better?
For most people, yes. Most stomach side effects happen while the dose is going up and ease once you've been on the same dose for a few weeks. Your Progress chart shows whether yours are fading.
Can Glapp tell me whether a side effect is serious?
No. Glapp organizes what you log; it doesn't diagnose. If you can't keep fluids down, have severe stomach pain or notice signs of an allergic reaction, contact your prescriber or get emergency care.
About the data
Ratings are self-reported and medication levels are estimated from dose and timing, not measured. Trial figures come from the prescribing information of FDA-approved tirzepatide and semaglutide for weight loss. App ratings were checked on November 8, 2026. This page is for information only and is not medical advice; talk to your prescriber about any side effect.
About the author
We're GLP-1 patients and health tech professionals, building Glapp in collaboration with doctors. About us
Sources
- Eli Lilly. Zepbound (tirzepatide) prescribing information: Table 1, dosage and administration, pharmacokinetics.
- Novo Nordisk. Wegovy (semaglutide) injection prescribing information: Table 3, dosage and administration, pharmacokinetics.
- Jastreboff AM, et al. Tirzepatide once weekly for the treatment of obesity (SURMOUNT-1). N Engl J Med. 2022;387:205–16.
- Wilding JPH, et al. Once-weekly semaglutide in adults with overweight or obesity (STEP 1). N Engl J Med. 2021;384:989–1002.
- Glapp on Trustpilot, the App Store and Google Play (ratings and reviews), checked November 8, 2026.