Weight loss · Once-weekly injection
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.
Pricing
One pen colour per step.
You start at 2.5mg and only move up, at least 4 weeks apart, if you and your clinician agree. Each price is a month of four weekly doses.
How it works
What it does in the body.
1Two 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
2Hunger 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.
3Digestion 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.
4Your 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
Once a week, a few minutes.
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
Is it right for me?
Who it suits, and what to expect.
May be considered if
All of these usually apply
- You're an adult, 18 or over, living in the UK.
- Your BMI is 30 or more, or 27 or more with a weight-related condition such as high blood pressure or type 2 diabetes.2
- You're ready to use it alongside changes to how you eat and move.
- A clinician judges it safe with your health history and medicines.
Not suitable if
Any one of these rules it out
- 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.
Not sure where you fit? You don't need to work it out yourself. The assessment asks the right questions, and a clinician checks your answers.
Most side effects 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 often short-lived.
Get help straight away if
These are rare, but need a doctor quickly.
- 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
Your options
Two injections, two tablets.
Figures are average weight loss at the highest dose in each medicine's main trial, alongside diet and activity. They come from different trials in different people, so they aren't a direct ranking. The one direct comparison: when tirzepatide (Mounjaro) and injected semaglutide (Wegovy) were tested head to head over 72 weeks, average weight loss was 20.2% and 13.7%.4
Mounjaro
Tirzepatide · Weekly injection20.9%over 72 weeks1- Acts on GIP and GLP-1
- Same day each week
Wegovy
Semaglutide · Weekly injection14.9%over 68 weeks3- Acts on GLP-1
- Same day each week
Common questions
Mounjaro, answered.
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?
Guides
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.