How Common Weight Loss Injections Are Administered
Both Wegovy (semaglutide) and Mounjaro (tirzepatide) are subcutaneous injections — meaning they are injected into the fatty tissue just beneath the skin, not into a muscle or vein. They come as pre-filled pens designed for self-injection, and most people inject once a week on the same day each week.
Common injection sites
The three most commonly used sites are the abdomen (stomach area), the front of the thigh, and the upper outer arm. All three are suitable for most people, though your prescriber or doctor may have given you specific guidance based on your individual circumstances. Check the patient information leaflet that came with your pen for the exact instructions recommended for your medicine.
Why rotation matters
Rotating your injection site — moving to a different area, or a different spot within the same area, each week — is widely recommended to help reduce the chance of skin reactions such as lumps, hardening, or irritation at the injection site. Repeatedly using the same spot can affect how the medicine is absorbed over time. A simple rotation pattern (for example, abdomen one week, thigh the next) helps keep the skin in good condition throughout your treatment.
Storing your pen
Correct storage is important. Both medicines are typically kept refrigerated before first use, then can be kept at room temperature for a period once in use — but always check the leaflet that came with your specific pen, as the exact guidance can vary between products and pen formats. Never use a pen that has been frozen or left in direct sunlight.
For a broader overview of how these medicines are used, see our guide to weight loss injections. If you are curious about the costs involved in ongoing treatment, our pages on weight loss injection prices and finding well-priced weight loss injections offer neutral, informational context.
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.
Keeping Track of Your Injection Routine with GLP Trackr
Staying consistent with a weekly injection schedule — and rotating sites correctly — is straightforward in principle but easy to lose track of in practice. That is where GLP Trackr is built to help.
The app's injection-site tracking and rotation feature lets you log which site you used for each injection, and then suggests your next rotation based on your history. There is no need to remember or write it down separately — the app keeps a running record so you always know where you injected last and where to go next.
Alongside site tracking, dose logging lets you record each injection with the date, time, and dose strength, giving you a clear history of every shot you have taken. And if a weekly injection day ever slips your mind, dose reminders can prompt you before you miss it — because consistency is one of the most important factors in getting the most from your treatment.
If you ever do miss a dose, do not make any decisions about what to do next on your own — contact your prescriber or doctor, who can advise based on your specific situation. The app lets you log a missed dose so you have an accurate record to bring to that conversation. GLP Trackr supports your journey; it is not a substitute for clinical guidance.
Explore everything the app can do for your injection routine and beyond in our weight loss injections hub. GLP Trackr is free to try — download it on the App Store or Google Play and start a 7-day free trial today.
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.
The most commonly prescribed weight loss injections are semaglutide (Wegovy) and tirzepatide (Mounjaro). Both are once-weekly subcutaneous injections available only on prescription. Which one is suitable for you is a decision for your prescriber or doctor.
Common injection sites are the abdomen, front of the thigh, and upper outer arm. Your prescriber or doctor may give specific guidance, and the patient information leaflet with your pen will include the recommended instructions for your particular medicine.
Yes — rotating sites each week is widely recommended to reduce the risk of skin reactions such as lumps or hardening and to support consistent absorption. Moving to a different area, or a different spot within the same area, is generally advised. Follow your prescriber's guidance.
Any decision about a missed dose should be made with your prescriber or doctor, not on your own. Contact them for advice specific to your situation. GLP Trackr lets you log a missed dose so you have an accurate record to share at your next appointment.
GLP Trackr logs each injection — date, time, dose, and site — and suggests your next rotation based on your history. Dose reminders help you stay on your weekly schedule, and your full injection log is always available to review or share with your prescriber.