What the Evidence Says About Side Effects for Each Medicine
Both medicines work on GLP-1 receptors, which slow gastric emptying and influence appetite-regulating pathways in the brain. This shared mechanism is why their side-effect profiles overlap so significantly — and why comparing them on tolerability is less straightforward than it might seem.
Mounjaro (tirzepatide)
Tirzepatide acts on both GIP and GLP-1 receptors. Commonly reported side effects include nausea, diarrhoea, vomiting, constipation, and indigestion. These are most often noticed in the days following a dose or after a dose increase, and many people find they ease as the body adjusts over several weeks. Injection-site reactions are also occasionally reported.
Wegovy (semaglutide)
Semaglutide acts on GLP-1 receptors. Its side-effect profile is similar: nausea, vomiting, diarrhoea, constipation, and abdominal discomfort are the most frequently mentioned. As with tirzepatide, these tend to be most pronounced early in treatment or following titration steps, and often lessen over time.
What the comparison really comes down to
Clinical trial data for the two medicines use different study populations and designs, which makes direct tolerability comparisons unreliable. Individual factors — your dose, your titration pace, what you eat, and your own physiology — have as much influence on how you feel as the choice of medicine itself. For a more detailed look at how these two medicines compare factually, see which GLP-1 has the fewest side effects and a broader look at side effects across weight-loss injections.
Both Mounjaro and Wegovy carry additional monitoring status, and any side effects you experience should be reported to your healthcare professional and, where applicable, to your national reporting scheme (such as the UK's Yellow Card scheme).
average weekly weight change in the first 16 weeks of Mounjaro & Wegovy use*
Tracking the right four numbers — weight, waist, protein and dose — turns a noisy chart into a clear story. That's the loop GLP-1 users keep coming back for.
AI Meal Tracking. Built for GLP 1 Appetites.
Point your camera at any meal and let our AI do the rest. Breakfast, doses, weight, mood all tracked in seconds.
Tracking How Your Body Responds — and Why It Matters
One of the most practical things you can do when side effects are a concern is to keep a consistent record of what you experience and when. Patterns that are hard to notice day-to-day — like nausea clustering in the 24 hours after a dose, or fatigue improving after a few weeks — become much clearer when you have logged data to look back on.
GLP Trackr's side-effect tracker is built for exactly this. You can log symptoms as they happen, note their severity, and see how they track alongside your dose history over time. That record becomes genuinely useful at your next prescriber appointment — rather than trying to recall how you felt three weeks ago, you have a clear timeline to share.
Alongside side-effect logging, the app's daily check-in captures mood, energy, and sleep in under a minute — useful context when you're trying to work out whether fatigue or low energy is related to the medicine or something else entirely. You can also find support from others navigating the same journey in the GLP Trackr community.
For a closer look at what to expect specifically with Mounjaro, the Mounjaro side effects guide covers the most commonly reported experiences in detail. You may also find it helpful to read about side effects reported with Wegovy if that is the medicine you have been prescribed.
If any side effect is severe, persistent, or feels worrying, contact your healthcare professional promptly. GLP Trackr helps you record what you're experiencing so you can have an informed conversation with your prescriber — it is not a substitute for their guidance, and any decisions about your treatment should always be made with them.
Start logging your symptoms and spotting your own patterns — download GLP Trackr free on the App Store or Google Play and try it for 7 days at no cost.
What does glptrackr include?
10+ powerful features. One app. Built specifically for Mounjaro and Wegovy users.
Everything your GLP-1 journey needs. Free to try for 7 days.
Morning Check-In
Start every day with a 60-second wellness check-in. Log how you're feeling, track nausea, appetite, energy, and mood — giving you and your care team a complete picture of how your medication is working.
Injection Tracking
Log every dose with a single tap. Track your dose history, phase in your cycle, estimated medication levels, and upcoming injection dates — with reminders so you never miss a scheduled shot.
Hydration Reminders
Staying hydrated is especially important on GLP-1 medications. Set daily water targets, log intake throughout the day, and receive smart nudges when you're falling behind your goal.
Smart Meal Planning
Personalized meal plans built around your current dose phase and side effects. Every meal is GLP-1 optimized — high in protein, gentle on the stomach, and scaled to your reduced appetite.
Recipe Library
Browse 50+ high-protein, GLP-1-friendly recipes filtered by meal type, prep time, and dietary needs. Every recipe includes full nutrition info, step-by-step instructions, and tips for eating with side effects.
Progress Analytics
Beautiful, easy-to-read charts show your weight loss trajectory, weekly nutrition trends, medication responses, and wellbeing scores over time — turning raw data into genuine insights.
AI Meal Scanning
Snap a photo of any meal and get a full nutrition breakdown in seconds — calories, protein, carbs, fat, and fibre. No searching. No manual logging. Just point, snap, and track.
Exercise & Steps
Log walks, workouts, and movement with activity targets that flex with your energy levels. On lower-energy dose days, gentler targets keep you moving without burning out.
Community Support
Connect with thousands of others navigating the same medication journey. Share milestones, ask questions, find accountability partners, and get support from people who truly understand.
Never Forget a Dose Again.
Log your Mounjaro or Wegovy injection in seconds. Track your pen, your dose level, and your injection site — so you always know exactly where you are in your treatment.
Watch Your Body Transform, Week by Week.
Log your weight, measurements, and how you're feeling after each dose. GLPTrackr turns your data into clear, motivating charts that show you how far you've really come.
You're Not on This Journey Alone.
Connect with thousands of real GLP-1 users sharing their wins, side effect tips, and meal ideas. Get the support of people who truly get it — because they're living it too.
Download on the App Store Download on the Google Play
Founding Member Offer
One plan. Everything included. No hidden extras.
Founding Member
Exclusive Offer
Join the first 1,000 membersand lock in our lowest ever price
Offer expires in:
786 of 1000 founding spots remaining
50% OFF
Lifetime Price Lock
Never pay full price • Forever
🔒 No credit card required • Cancel anytime
Premium
Ad-free- Track weight, meals, water, exercise, & sleep
- Log doses, injection sites, & side effects
- 60-second daily morning check-in
- AI meal scanning & barcode scanning
- Personalised AI meal plans & recipes
- Golden Dose Finder AI
- Medication Clock — real-time level tracking
- Daily Brief and predictive side effects
- Full insights & weekly transformation cards
- Unlimited progress photos
- Doctor PDF export & body measurements
- Community Access—Connect with GLP-1 users
Powered by
🔒 No credit card required • Cancel anytime
The Most Advanced GLP-1 Brain Ever Built.
The first AI built exclusively for GLP-1 weight loss. Every insight, every meal plan, every prediction trained on one thing only: helping you get the most out of your medication.
Knows Your Cycle
GLPIQ tracks where you are in your injection cycle and adjusts everything around it: lighter meals on nausea days, higher protein when appetite returns, and smarter targets as your medication level shifts.
Predicts Before You Feel It
GLPIQ learns your personal side effect patterns over time. After a few cycles, it starts warning you the morning before a rough day — and adjusts your meal plan automatically.
Finds Your Golden Dose
GLPIQ analyses every dose you've been on: weight loss rate, side effects, food noise, mood, protein adherence and tells you which dose gave you the best results. No other app does this.
Download glptrackr today.
Available on iOS and Android. 7-day free trial, no credit card needed.
Frequently asked questions.
Both Mounjaro (tirzepatide) and Wegovy (semaglutide) most commonly cause gastrointestinal effects such as nausea and constipation. Neither is definitively gentler for everyone — individual response varies widely. Your prescriber or doctor is best placed to advise on which medicine is more suitable for you.
The side-effect profiles of Mounjaro and Wegovy are broadly similar, as both affect GLP-1 pathways. Mounjaro also acts on GIP receptors. Nausea, diarrhoea, constipation, and indigestion are commonly reported with both. How any individual experiences them depends on many personal factors.
Many people find that gastrointestinal side effects are most noticeable shortly after starting or after a dose increase, and that they ease as the body adjusts over several weeks. This is not universal — if symptoms are persistent or severe, speak with your healthcare professional.
Contact your healthcare professional promptly if any side effect is severe, does not improve, or feels unusual. This includes persistent vomiting, severe abdominal pain, or any symptom that concerns you. Never rely on an app or website to assess whether a symptom is serious.
GLP Trackr lets you log symptoms, note severity, and view them alongside your dose history over time. This makes it easier to spot patterns and gives you a clear record to share with your prescriber at appointments.