Our goal is to help you find the option that’s right for your needs, and guide you through the change with expert support.
Switching medications is a normal and common occurrence — it’s something medical professionals recommend regularly for conditions like high blood pressure or high cholesterol, whether it’s to reduce side effects or lower costs.
However, you may not need to switch from Mounjaro, but instead explore a lower dose. We’ll work with you to find the solution that’s right for your needs, budget and goals.
Both Wegovy (semaglutide 7.2mg) and Mounjaro (tirzepatide 15mg) are highly effective for long-term weight loss, but they work slightly differently and may affect people differently.
In 72 weeks, people taking Wegovy 7.2mg in a clinical study lost an average of 20.7% of their body weight when taken as directed. This means that someone who weighs 100kg may lose 20.7kg on average in 72 weeks (1 year, 5 months).*
In 72 weeks, people taking Mounjaro 15mg in a clinical study lost an average of 22.5% of their body weight when taken as directed. This means that someone who weighs 100kg may lose 22.5kg on average in 72 weeks (1 year, 5 months).**
These are examples only. It is not a prediction of individual results.
Both can be excellent options. The right choice comes down to your health needs, goals, lifestyle and how your body responds to treatment. Our medical team will help you find what works best for you.
*STEP UP, 72-week study of adults with obesity using Wegovy (semaglutide 7.2mg). Individual results vary.
**SURMOUNT-1, 72-week study of adults with obesity using Mounjaro (tirzepatide 15mg). Individual results vary.
Wegovy and Mounjaro work in similar ways, so some people experience similar side effects. The most common are digestive effects such as nausea, vomiting, diarrhoea, constipation and stomach discomfort.
Side effects are usually mild to moderate and often improve as your body adjusts to treatment.
If you tolerated Mounjaro well, you may have a similar experience on Wegovy. However, everyone responds differently depending on the dose and individual factors. Your clinician will review your health and treatment history before switching, to help you move safely and comfortably.
A note about the higher Wegovy 7.2mg doseThe highest dose of Wegovy (7.2mg) can sometimes cause a temporary side effect called dysesthesia. This can feel like tingling, pins and needles, buzzing, or a mild burning sensation on the skin. It is not nerve damage and usually improves over time, even while continuing treatment.
In clinical studies:
Most side effects were mild to moderate and settled over time. Your care team will monitor your response closely and can adjust your dose if needed to help manage side effects and keep your treatment safe and comfortable.
More questions? See all FAQs
You don’t need to start over. Our clinicians can help find you a suitable Wegovy dose based on your current Mounjaro dose and tolerance.
Mounjaro and Wegovy work differently in the body, so their doses don't translate directly. There isn't currently any published research that shows how to convert a dose from one treatment to another. Because of this, switching between them isn't about finding an "equivalent" dose. Instead, your prescriber focuses on:
Everyone responds differently. If you switch from Mounjaro to Wegovy, you may need to start at a lower dose and build up again. Your MedExpress prescriber will explain your options and help you decide the best next step.
 Wegovy® (semaglutide) |  Mounjaro® (tirzepatide) |
|---|---|
Price range £69.99–£159.99 | Price range £179.99–£309.99 |
Average weight loss (in clinical studies)* 20.7% of body weight | Average weight loss (in clinical studies)* 22.5% of body weight |
Treatment schedule Weekly injection | Treatment schedule Weekly injection |
Dose adjustments Gradual, guided by your clinician | Dose adjustments Gradual, guided by your clinician |
Suitable for oral contraception? Yes | Suitable for oral contraception? No |
Injection site reactions (in studies)** Reported in 5% of participants | Injection site reactions (in studies)** Reported in 4.4% of participants |
Heart health indication*** Approved to reduce the risk of heart disease in adults with obesity or overweight and existing heart conditions | Heart health indication*** Not currently licensed for this use |
*Effectiveness: In 72 weeks, people taking Mounjaro 15mg in a clinical study lost an average of 22.5% of their body weight when taken as directed. This means that someone who weighs 100kg may lose an average of 22.5kg in 72 weeks (1 year, 5 months).
In 72 weeks, people taking Wegovy 7.2mg in a clinical study lost an average of 20.7% of their body weight when taken as directed. This means that someone who weighs 100kg may lose 20.7kg on average in 72 weeks (1 year, 5 months).
These are examples only and not a prediction of individual results.
**In SURMOUNT-1, the pooled average for injection site reactions from 2,539 participants was 4.4% with Mounjaro. For Wegovy, this was 5.0% in the STEP-1 clinical trial of 1,961 participants.
***Heart health: Clinical trials show Wegovy can reduce the risk of heart attack, stroke and death from heart disease by up to 20% in people with obesity or who are overweight and have existing heart disease, even if they don’t have diabetes.
I had tried every diet under the sun. I finally plucked up the courage… and it has changed my life. I am happier, more confident, full of energy and able to run around after my children for longer. [It] has drastically improved my physical, emotional and mental health.
I was starting to get a pain in my knee which seems to have decreased a lot since losing the weight. I don't get any more back pain. It's made me a lot more confident within myself. I actually want to go out and do things. I want to go clothes shopping. I want to enjoy things with my kids.
I can do more. I feel more energetic. I can play more with my kids, whereas before I was restricted. It's mostly the breathlessness, the being slow, being out of breath, feeling heavy, not being able to put my clothes on properly because they were too tight. It's been a brilliant experience with MedExpress.
I used to hide away in oversized clothes, just trying to feel comfortable—but I had no confidence. Now, I'm fitting back into clothes I haven't worn in years, and I actually enjoy getting dressed in the morning. I feel happier, more confident, and like I'm finally showing up as myself.
It's making me more happy about myself. I'm feeling more confident. I'm not hiding. If my friend invites me for a coffee, I won't say no anymore. I'm dressing-up! I'm taking care of myself now. I feel more happy every day. I'm more talkative. I'm going to more family events.
These customers received compensation for sharing their experience.
In anonymised MedExpress data, people prescribed Mounjaro lost an average of around 20% of their body weight after 12 months. Individual results vary.
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Authored by Dr Zoë Lees. Last reviewed 16 February 2026 by Liyya Patel.