Mounjaro Weight Loss Injection
It’s licenced in the UK for weight loss and weight maintenance, where studies have shown patients can lose up to 25% of their starting body weight. Once a week .
UK-registered clinical team- Confidential & secure
- No GP visit needed
- Fast & discreet delivery
Mounjaro Injections (tirzepatide)
Mounjaro Injections (tirzepatide) Product information
£148.99 (£148.99 per units)
| 2.5mg | 5mg | 7.5mg | 10mg | 12.5mg | 15mg | |
|---|---|---|---|---|---|---|
| 1 units | £148.99 | £189.99 | £248.96 | £278.96 | £289.98 | £299.98 |
Mounjaro KwikPen
The Mounjaro KwikPen contains Tirzepatide, a medication that’s proven to help reduce appetite and curb cravings to support weight loss. It can also be used for weight loss maintenance once you’ve reached your weight loss goal.
- Lose up to 25% of your body weight
- 4 week supply of Tirzepatide injections per pen
- Expert on-hand weight management support
Time for a change?
Thinking about switching your weight loss treatment from Mounjaro to Wegovy? Explore our switching guide to see how.
Explore weight management options with confidence at Oxford Online Pharmacy. We’re trusted by over 30,000 patients who’ve rated us 5 stars on Trustpilot.
Product Information for Mounjaro Injections (tirzepatide)
Get to know the Mounjaro KwikPen
Using the active ingredient Tirzepatide, the Mounjaro KwikPen is part of a family of new-generation weight loss treatments. It’s licenced in the UK for weight loss and weight maintenance, where studies have shown patients can lose up to 25% of their starting body weight.
- Once a week injection with a self-administer pen
- Sourced direct from manufacturer (Eli Lilly)
Mounjaro KwikPen key facts
The pen is designed to allow you to easily self-inject Mounjaro at home once a week. It’s injected just under the skin with a small, thin needle. You can choose to inject in either your stomach area, thigh or upper arm – whichever you prefer.
Each pen lasts one month and comes pre-loaded with 4 doses (4x once weekly injections).
Always make sure to read the user instructions and the Patient Information Leaflet that comes with the device.
How do Mounjaro injections work?
Mounjaro injections work by mimicking two hormones your body naturally makes: GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide). These hormones help control blood sugar levels and reduce hunger.
How Mounjaro works with your body
Mounjaro works with your body to help you lose weight. It’s most effective when used alongside a balanced, healthy diet and increased physical activity or exercise.
- Helps your pancreas make insulin: After you eat, Mounjaro tells the pancreas to release more insulin, a hormone that lowers blood sugar. Improving how your body uses insulin stops it from storing excess sugar as fat.
- Lowers the amount of sugar your liver makes: When your liver isn’t releasing sugar into the blood for energy, your body has to rely on fat stores for energy. This process, where the body breaks down its fat cells, is called lipolysis and leads to weight loss.
- Makes you feel full: Mounjaro works on the part of the brain that controls hunger, helping you feel full sooner and reducing how much you eat.
- Slows digestion: Mounjaro makes food move more slowly through the stomach, which helps prevent big spikes in blood sugar after meals and keeps you feeling full.
Understand who can use Mounjaro
Mounjaro is a prescription-only medication licenced in the UK for weight loss. This means there are guidelines on who it’s suitable for, based on a range of health factors and likelihood of successful treatment results.
It might be a suitable treatment for you if you meet the below initial eligibility criteria:
- Adults aged 18-85
- Those with a BMI above 30
- Those with a BMI above 27 and a weight-related condition such as high blood pressure, high cholesterol, heart disease, type 2 diabetes and some other weight-related health conditions
This list is only intended as an indicator for who might be suitable for treatment. The doctor will complete a full medical review of your consultation to determine your individual suitability for treatment.
Use this NHS tool to calculate your BMI.
Possible Mounjaro weight loss results
Studies have shown a possible weight loss of up to 25% over 88 weeks. Mounjaro is a long-term weight loss treatment and not just a short-term option, you should start to see weight loss within the first 4-6 weeks.
Weight loss examples
One medical trial involved 2,539 people using either a placebo, Mounjaro 5mg, Mounjaro 10mg or Mounjaro 15mg once a week for 72 weeks (just over 1 year and 4 months).
Everyone using Tirzepatide (Mounjaro) on the trial started with 2.5mg once weekly for the first four weeks. During this time, they lost around 3% of their starting body weight.
Tirzepatide users on the trial went up to 5mg once weekly for the next four weeks (weeks 5-8). During this time, users reached an average of 5-6% weight loss.
For weeks 9-12, some people stayed on 5mg of Mounjaro, and some moved up to 7.5mg weekly. Most people lost around 8% of their starting weight by week 12, regardless of whether they were on 5mg or 7.5mg.
Remember, studies show an example of what’s possible, but every weight loss journey is unique.
Our expert team is here to help you achieve your health and weight goals.
Important – Before taking any medication, it is always important to read the Patient Information Leaflet (PIL)
Mounjaro Injections (tirzepatide) – Patient Information Leaflet
- Jastreboff AM, Aronne LJ, Ahmad NN, Wharton S, Connery L, Alves B, et al. Tirzepatide Once Weekly for the Treatment of Obesity. New England Journal of Medicine [Internet]. 2022 Jun 4;387(3):205–16. Available from: https://www.nejm.org/doi/full/10.1056/NEJMoa2206038. Retrieved December 2, 2025.
- Aronne LJ, Sattar N, Horn DB, Bays HE, Wharton S, Lin WY, et al. Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity: The SURMOUNT-4 Randomized Clinical Trial. JAMA [Internet]. 2023 Dec 11;331(1). Available from: https://jamanetwork.com/journals/jama/fullarticle/2812936. Retrieved December 2, 2025.
- Skelley JW, Swearengin K, York AL, Glover LH. The impact of tirzepatide and glucagon-like peptide 1 receptor agonists on oral hormonal contraception. Journal of the American Pharmacists Association. 2023 Nov 1;64(1). Available from: https://pubmed.ncbi.nlm.nih.gov/37940101/. Retrieved December 2, 2025.
- Lin F, Yu B, Ling B, Lv G, Shang H, Zhao X, et al. Weight loss efficiency and safety of tirzepatide: A Systematic review. PloS One [Internet]. 2023;18(5):e0285197. Available from: https://pubmed.ncbi.nlm.nih.gov/37141329/. Retrieved December 2, 2025.
- ClinicalTrials.gov [Internet]. clinicaltrials.gov. Available from: https://clinicaltrials.gov/study/NCT04184622. Retrieved December 2, 2025.
- Lilly’s SURMOUNT-2 results published in The Lancet show tirzepatide achieved a mean weight reduction of 15.7% at the highest dose (15 mg) in adults with obesity or overweight and type 2 diabetes | Eli Lilly and Company [Internet]. Eli Lilly and Company. 2022. Available from: https://investor.lilly.com/news-releases/news-release-details/lillys-surmount-2-results-published-lancet-show-tirzepatide. Retrieved December 2, 2025.
- Package leaflet: Information for the patient Mounjaro ® 2.5 mg KwikPen ® solution for injection in pre-filled pen Mounjaro ® 5 mg KwikPen ® solution for injection in pre-filled pen Mounjaro ® 7.5 mg KwikPen ® solution for injection in pre-filled pen Mounjaro ® 10 mg KwikPen ® solution for injection in pre-filled pen Mounjaro ® 12.5 mg KwikPen ® solution for injection in pre-filled pen Mounjaro ® 15 mg KwikPen ® solution for injection in pre [Internet]. Available from: https://www.medicines.org.uk/emc/files/pil.15481.pdf. Retrieved December 2, 2025.
- Instructions for use injection, for subcutaneous use Multi-dose single-patient-use pre-filled pen Each pen contains 4 fixed doses, one dose taken weekly. Mounjaro ® 2.5 mg KwikPen ® solution for injection in pre-filled pen Mounjaro ® 5 mg KwikPen ® solution for injection in pre-filled pen Mounjaro ® 7.5 mg KwikPen ® solution for injection in pre-filled pen Mounjaro ® 10 mg KwikPen ® solution for injection in pre-filled pen Mounjaro ® 12.5 mg KwikPen ® solution for injection in pre-filled pen Mounjaro ® 15 mg KwikPen ® solution for injection in pre-filled pen tirzepatide This Instructions for Use contains information on how to inject Mounjaro KwikPen [Internet]. [cited 2025 Dec 2]. Available from: https://www.medicines.org.uk/emc/files/usermanual.15482.pdf. Retrieved December 2, 2025.
Some people taking GLP-1 injections for weight loss have reported temporary blurred vision. This can happen during the first few weeks of treatment and is usually due to changes in blood sugar levels, or dry eyes caused by dehydration.
There’s usually nothing to worry about, but if you experience any sudden or severe changes to your vision, contact your optician immediately (NHS 111 for out-of-hours) and let them know you’re taking a GLP-1 weight loss medication.
If you have any questions or concerns about starting your treatment then please get in touch with us and a pharmacist will be available to advise you.
- What is GLP-1, and what does it have to do with weight?
- Wegovy vs Mounjaro: What’s the difference?
- £20 off your first weight loss order
- Mounjaro Price Hike: What It Means for UK Patients
- Real-world GLP-1 results: what we’re seeing and what it means
- Is my goal weight too low?
- I’m not losing weight yet – is my GLP-1 working
- Do I really have to count calories on a GLP1?
- How to eat well when you’re not hungry on a GLP-1
- Tools to support your first month on GLP-1 treatment
Authored on December 1, 2025
Reviewed on December 1, 2025
