Mounjaro injections for weight loss
Mounjaro (tirzepatide) is a prescription-only injection for weight management in adults, used alongside a reduced-calorie diet and more activity.2
From £149 a month
Check your eligibility →- CQC registered
- UK-registered clinicians
- Plain, discreet delivery
All content on this page has been medically reviewed by Naeem Teni, Clinical Lead. GPhC 2215591.
What is Mounjaro?
Mounjaro is a prescription-only medicine containing tirzepatide. It comes as a pre-filled pen you use once a week, and in the UK it is licensed for weight management in adults, used alongside a reduced-calorie diet and more activity.2
It is one of two weekly injections we prescribe. A clinician reviews your assessment before anything is prescribed, and stays with you as your dose changes.
How does Mounjaro work?
Tirzepatide copies two natural gut hormones that your body releases after eating. Together they change how hungry you feel and how your body handles food:
- Two hormones, not one. Tirzepatide acts on two gut-hormone receptors, GIP and GLP-1. Both play a part in how your body signals fullness after eating and how it handles blood sugar.2
- Hunger turns down. It works on the signals that tell your brain you've had enough. For many people that means less hunger between meals and feeling full sooner, so eating less takes less effort.
- Digestion slows. It slows how quickly your stomach empties, so food stays with you longer. That fuller, steadier feeling is part of why portions start to shrink on their own.
- Your changes do the rest. It supports changes to how you eat and move rather than replacing them. In trials, weight tended to return when treatment stopped, which is why lasting habits matter.5
What is the dosing schedule for Mounjaro?
Every strength comes in its own colour pen. You start at 2.5mg and only move up, at least four weeks apart, if you and your clinician agree.2
You don't have to reach the highest dose. Plenty of people stay on a lower one that works for them. Each price covers a month of four weekly doses, with the care around it included.
Check your eligibility →
How do I use Mounjaro?
One injection, once a week, takes a few minutes. Your clinician can talk you through the first one.
- Pick your day. Inject on the same day each week, at any time, with or without food.2
- Choose a spot. Your stomach (at least 5cm from your belly button), thigh, or upper arm if someone helps. Use a different spot each week.
- Inject. Fit a new needle every time, dial your dose, and follow the leaflet step by step. Your clinician can talk you through the first one.
- Store it right. Keep pens in the fridge at 2–8°C and never freeze them. A pen can be kept out of the fridge, below 30°C, for up to 30 days.2
Missed a dose? Take it as soon as you remember if it's within 4 days. If it's later than that, skip it and take your next one on your usual day.2
How does Mounjaro compare with other options?
These figures come from each medicine's main trial at its highest dose, in different groups of people, so they aren't a direct ranking. The one head-to-head trial found average weight loss of 20.2% with tirzepatide and 13.7% with injected semaglutide over 72 weeks.4
| Mounjaro | Wegovy | Wegovy Pill | Foundayo | |
|---|---|---|---|---|
| Active ingredient | Tirzepatide | Semaglutide | Semaglutide | Orforglipron |
| How you take it | Weekly injection | Weekly injection | Daily tablet | Daily tablet |
| Acts on | GIP and GLP-1 | GLP-1 | GLP-1 | GLP-1 |
| Average weight loss in main trial | 20.9% over 72 weeks1 | 14.9% over 68 weeks3 | 13.6% over 64 weeks6 | 11.2% over 72 weeks7 |
| From | £149 a month | £119 a month | £99 a month | See pricing |
| This page | View Wegovy → | View Wegovy Pill → | View Foundayo → |
Is Mounjaro right for me?
It isn't suitable for everyone. Your assessment covers all of this, and a clinician checks your answers before anything is prescribed.
Usually suitable if
- You're 18 or over and live in the UK
- Your BMI is 30+, or 27+ with a weight-related condition such as high blood pressure or type 2 diabetes2
- You'll use it alongside changes to how you eat and move
Not suitable if
- You're pregnant, planning a pregnancy, or breastfeeding
- You have a history of medullary thyroid cancer or MEN 2
- You're allergic to tirzepatide or any of its ingredients
- You have certain conditions, such as severe gastrointestinal disease
Quick check
What's my BMI?
BMI is only a guide. A clinician looks at your whole health history.
What are the side effects of Mounjaro?
Most are mild, happen early on or after a dose increase, and ease with time. Your clinician is there if they don't.2
More common
Usually mild and short-lived
Rare
Get medical help straight away if you have
- Severe stomach pain that won't go away, sometimes reaching your back
- Pain in the upper right of your stomach, fever, or yellowing skin or eyes
- Vomiting or diarrhoea that stops you keeping fluids down
- Swelling of your face, lips or throat, or trouble breathing
On the contraceptive pill? Mounjaro can make it less reliable. Use a barrier method such as condoms as well for 4 weeks after starting, and for 4 weeks after each dose increase.2
Mounjaro FAQs
Is Manova a proper clinic, or a website?
Will it turn up in a branded box at my office?
What if the clinician says no?
Am I locked into a contract?
How is this different from going to my GP?
Read up on Mounjaro
References (7)
- Jastreboff AM, et al. Tirzepatide once weekly for the treatment of obesity (SURMOUNT-1). N Engl J Med. 2022;387:205–216.
- Mounjaro KwikPen Summary of Product Characteristics. Eli Lilly and Company Ltd. Electronic Medicines Compendium (EMC).
- Wilding JPH, et al. Once-weekly semaglutide in adults with overweight or obesity (STEP 1). N Engl J Med. 2021;384:989–1002.
- Aronne LJ, et al. Tirzepatide as compared with semaglutide for the treatment of obesity (SURMOUNT-5). N Engl J Med. 2025.
- Aronne LJ, et al. Continued treatment with tirzepatide for maintenance of weight reduction in adults with obesity (SURMOUNT-4). JAMA. 2024;331(1):38–48.
- Wharton S, et al. Oral semaglutide at a dose of 25 mg in adults with overweight or obesity (OASIS 4). N Engl J Med. 2025;393(11):1077–1087.
- Wharton S, et al. Orforglipron, an oral small-molecule GLP-1 receptor agonist for obesity treatment (ATTAIN-1). N Engl J Med. 2025;393(18):1796–1806.