Both Mounjaro and Wegovy are highly effective GLP-1 medications for weight loss. While many people stay on one medication throughout their journey, there are times when switching can make sense.
In clinical trials, Mounjaro has shown 22.5% average weight loss at its highest dose. Wegovy's 7.2mg dose achieves 20.7% average weight loss, with one in three people losing 25% or more. They work in similar ways, but everyone responds differently, which may mean one is more suitable for you.
Here's what to know about switching from Mounjaro to Wegovy (or Wegovy to Mounjaro) safely, what to expect during the transition, and how we support you through the process.
Why consider switching?
There are several reasons you might want to switch between these GLP-1 medications:
Progress has plateaued
If your weight loss has slowed or stalled, switching medications can sometimes help restart your progress. While both medications are highly effective, everyone responds differently, and you may find one medication works better for you than the other.
Managing side effects
While both medications have similar side effect profiles, individual tolerance can vary. If you're finding it difficult to manage side effects on your current medication despite lifestyle adjustments and giving it time, you may tolerate the other option better.
Heart health considerations
If you have established cardiovascular disease alongside obesity, medication choice may matter for your heart health. Wegovy is currently the only GLP-1 medication licensed in the UK to reduce the risk of major cardiac events like heart attack and stroke, based on results from the SELECT CVOT trial. Mounjaro has also shown cardiovascular benefits in clinical trials, though it's not yet approved for this indication in the UK.
Mounjaro vs Wegovy
Here’s a quick comparison of Wegovy and Mounjaro:
*The Mounjaro price shown above is for new Voy customers only.
How to switch between Mounjaro and Wegovy
Switching medications can feel daunting, but with the right support, the transition can be smooth and safe. The process is the same whether you're switching from Mounjaro to Wegovy or from Wegovy to Mounjaro.
Where to start
- Already with Voy: Open the Voy app and request a switch on the "Plan" page where you will be prompted to complete a short medical assessment.
- New to Voy or switching from another provider: Complete our quick eligibility questionnaire, and we’ll guide you through the switch.
Step 1 - Complete your short assessment
We’ll check for any updates since you started treatment, including changes to your medical history, any side effects you’ve experienced, your last dose strength, and when you last took it. This helps us make sure your switch is safe and maintains your progress.
Step 2 - Select your starting dose
Based on your answers, we’ll recommend two options:
- An equivalent dose, if you’ve been tolerating treatment well and want to keep momentum
- A lower, gradual starting dose, if you’ve had recent side effects or want to ease into treatment
Every dose plan is reviewed by a clinician before approval, and you’re free to choose a lower dose if you prefer.
Step 3 - Clinician review and approval
Your answers and previous treatment journey will be reviewed by a clinician to confirm it's safe to proceed with the switch. If everything checks out, your prescription will be approved.
Step 4 - Receive your medication
Once approved, your medication will be delivered straight to your door in secure, discreet packaging.
Remember to store your medication correctly:
- Wegovy storage guidance: Keep in the fridge (2–8°C) until first use. After opening, store in the fridge or at room temperature (below 30°C) and use within 6 weeks.
- Mounjaro storage guidance: Keep in the fridge (2–8°C) until first use. After opening, store in the fridge or at room temperature (up to 30°C) and use within 30 days.
Step 5 - When switching from Mounjaro to Wegovy (or Wegovy to Mounjaro): wait one week
Allow at least 7 days between your final dose of one medication and your first injection of the other. Ideally, begin on your usual injection day to keep your routine consistent.
Step 6 – Begin your new medication
Start with your approved dose.
Key differences to remember:
- Wegovy: Prime your pen before the first use only
- Mounjaro: Perform a flow check (priming) before every dose, not just the first
Step 7 – Check in with us
We'll follow up after your first injection to see how you're feeling and make sure everything is going smoothly. You're also welcome to reach out anytime. You can speak to one of our clinicians within minutes via live chat or the hotline if you have any questions or concerns.
Dose conversion: switching from Mounjaro to Wegovy or Wegovy to Mounjaro
Wondering what dose you'll start with? The tables below show typical starting doses when switching. Your clinician will review your treatment history and recommend the most appropriate dose for you, which may be lower if you've missed doses or experienced side effects.
Switching from Mounjaro to Wegovy
Switching from Wegovy to Mounjaro
*Current dose refers to the dose you are prescribed at the time of switching.
Is it safe to switch between Mounjaro and Wegovy?
Yes, switching between GLP-1 medications is safe when done with clinical guidance. Most people do well with the transition, but it’s normal to experience:
- Mild side effects like nausea or digestive discomfort, especially in the first few weeks as your body gets used to the new medication. Mounjaro side effects are similar to Wegovy side effects.
- A short adjustment period while your system adapts
At Voy, we carefully review your full treatment history, including your dose, progress so far, side effects, and your personal goals. This allows us to recommend a safe switch and the most appropriate starting dose for you.
Side effects support at Voy
"If you're using Voy and you experience any side effects, rest assured that our expert clinicians are just a message or phone call away. They can adjust your dose, prescribe medication to ease your symptoms, or simply offer reassurance.
Everyone responds differently to weight loss treatment and we'll help you find what feels right for you."
Can you switch without losing progress?
Yes. While some people notice a brief pause in weight loss after switching, this is usually temporary. In fact, switching can sometimes help you move forward, especially if you’ve plateaued or struggled with side effects.
If your new medication is better tolerated, it may allow you to increase your dose more smoothly and stay consistent, both of which can support better results over time.
And if you're not just switching medications but changing your weight-loss provider entirely, here’s a step-by-step guide to make the transition smooth and safe.
Consistency with your habits and patience with your body goes a long way. Everyone’s journey is different, but with the right support, switching doesn’t have to mean starting over. Our team is here to guide you every step of the way.
Why switch with Voy?
At Voy, we make switching medications simple, safe, and fully supported. Whether you're continuing your journey or starting fresh, we're here to guide you every step of the way.
Research shows that people lose more weight on Voy’s weight-loss programme, regardless of which medication they’re taking. Participants who used Voy regularly lost up to 53% more weight by month four when engaging with the programme, showing that active participation really makes a difference.
Here’s what sets us apart:
- Free, fast delivery – Your medication arrives quickly in secure, discreet packaging
- Support within minutes – Speak to a clinician via our hotline or live chat whenever you need help
- Smart in-app tools – Track your weight, appetite, and progress, log injection days, and access expert advice through videos, tips, and nutrition content
- 1-to-1 personalised coaching – Get support tailored to you across nutrition, lifestyle, and behaviour change
- Money-back guarantee – If it’s not the right fit, we’ll help you find an option that is or refund your plan
Thousands of people trust Voy for safe, clinically backed weight loss support and we’re here to help you reach your goals too.
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