Mounjaro
A once-weekly, self-administered injection designed to help you lose weight
Lose up to 22.5% of your body weight
Mimics GLP-1 and GIP, to reduce appetite and cravings
Free clinical support throughout your treatment
Weight management may be suitable for patients with a BMI of 25 or more
- Free Delivery
- Clinical Reviews
- Easy to Manage
- Track your Savings
Mounjaro Price
Mounjaro costs depend on your dose. We regularly check our prices against other pharmacies, so you get the best value when you buy Mounjaro online with us. Here’s what you’ll pay per month at each dose.
Save £20 every month
Subscribe & Save on popular treatments
Never miss your next dose. Your treatment can be prepared automatically every month, with a quick check-in before each order.
Subscribe & Save
Best Value
- Auto-renews every 4 weeks
- Quick monthly check-in
- Choose to stay on the same dose, increase, decrease, or pause
- Cancel anytime
One-time purchase
Best Value
- Single order only
- No ongoing savings
- Reorder manually each month
What is Mounjaro and how does it work?
Mounjaro is a prescription-only weight loss injection licensed by the MHRA that helps you lose weight and supports long-term weight management. You self-inject Mounjaro once a week with a pre-filled pen that contains four doses. This means that a pen should last you for four weeks.
Mounjaro contains the active ingredient tirzepatide. It works by mimicking the action of two hormones: GLP-1 and GIP. Together they reduce cravings, appetite and slow digestion, so you feel fuller for longer. In a head to head trial (SURMOUNT-5), people taking tirzepatide lost more weight on average than people taking semaglutide: 20.2% vs 13.6% after 72 weeks.
Mounjaro weight loss injections work best when paired with lifestyle changes, such as eating a balanced diet, maintaining a calorie deficit, and exercising regularly.
Your journey
starts here
More than medication. Our pharmacists provide expert support designed to help you succeed.
Start Free Consultation
Complete a quick, free online questionnaire.
Clinician Review
After you choose your preferred treatment, our clinicians will review your consultation.
Delivered to your door
Your medication is approved and delivered quickly in discreet packaging.
Access your coaching
Activate your access code in the Nutrable app to access personalised nutrition guidance and coaching features.
“Every consultation is reviewed carefully to ensure treatment is safe, appropriate, and tailored to the individual. Patient wellbeing is always our priority.”
Dr James Paweleck – Medical Director
What’s in your Mounjaro order
You can only buy Mounjaro after a qualified clinician reviews your consultation. If we approve your treatment, you’ll get clear guidance and ongoing support while you’re with us.
With your order, you’ll receive:
- Your Mounjaro pen, prefilled with your prescribed dose
- Four single-use needles
- A sharps bin
- A patient information leaflet
- Easy progress tracking, practical nutrition advice and support with the Nutrable app
- Clinical support to answer any questions you have during your treatment; we’re always happy to help
Mounjaro doses
Mounjaro weight loss injections are available in six dose strengths. Treatment always starts at the lowest dose of 2.5 mg so your body has time to safely adjust. You stay on each dose for at least 4 weeks before increasing by 2.5mg, and only if your clinician agrees it is right for you.
From there, you’ll gradually increase the dosage until you reach your maintenance dose. This might be at the highest dose of 15mg or lower. It depends on what gets you the best weight loss results with the fewest side effects.
You can see an example of the Mounjaro dosing schedule below:
How effective is Mounjaro?
In clinical trials, people using Mounjaro weight loss injections lost different amounts of weight over 72 weeks, depending on the dosage. When paired with regular exercise and a calorie deficit, the higher the dose, the more weight people lost:
5mg dose – 15.0% average weight lost
10mg dose – 19.5% average weight lost
15mg dose – 20.9% average weight lost
People taking a placebo lost an average of 3.1% of their body weight.
For example, someone starting at 100kg could lose around 21kg on average after 72 weeks on the 15mg dose (after titrating up). Some people lose more, some people lose less.Your results will depend on your starting weight, how closely you stick to your diet, and whether you exercise.
Eligibility
Who can take Mounjaro?
Mounjaro is licensed for adults who meet specific clinical criteria and can use them safely under medical supervision. You may be eligible if you:
- Have a BMI of 30 kg/m² or above
- Have a BMI of 27–30 kg/m² with a weight-related condition such as high blood pressure, high cholesterol, pre-diabetes, or heart disease
- Are from an ethnic background, where lower BMI thresholds may apply (typically from 27.5 kg/m²) due to higher metabolic risk. Those from such a background whom also have a weight-related condition may be eligible with a BMI of 25kg/m² or above
- Are transferring from another provider and want to continue treatment with us. You will need evidence that you met these criteria when you started, plus evidence of your recent prescription
When assessing whether treatment is right for you, our clinicians take your individual health risks into account, including your family background.
To get started, complete an online consultation, answering a few questions about your health and medical history. It takes only a few minutes, and one of our clinicians will review your answers to ensure Mounjaro is safe and suitable for you.
Who cannot use Mounjaro?
Mounjaro isn’t suitable if you:
- Are pregnant, planning a pregnancy, or breastfeeding (stop Mounjaro at least 1 month before you try to get pregnant)
- Are under 18 (those ages over 85 may be considered after review by a prescriber)
- Have a severe stomach or gut condition, such as severe gastroparesis
- Have certain types of diabetic retinopathy
- Have had pancreatitis
- Are allergic to tirzepetide or any of the other ingredients
Tell our clinicians if you take insulin or a sulfonylurea (such as Gliclazide), take warfarin or another medication that needs carefully monitoring, or are due to have an operation or procedure under general anaesthetic or sedation.
Average weight loss on different Mounjaro doses
Key points about Mounjaro weight loss injection results:
Early on (2–4 weeks): your appetite drops and portion control improves.
Progressive weight loss (8–12 weeks): you’ll usually see visible weight loss as the dose is increased safely.
Maximum results (up to 72 weeks): clinical studies show up to 22% body weight loss on the highest dose, alongside lifestyle changes.
Dose escalation matters: Gradual increases help minimise side effects and improve long-term results.
Best outcomes: come when you combine Mounjaro injections with a balanced diet and at least 150 minutes of activity a week.
Additional benefits: improvements in waist size, blood pressure, cholesterol and insulin sensitivity.
How to take and storage
How to inject Mounjaro
Always read the package leaflet that comes with your Mounjaro KwikPen before you start.
Timing: once a week, ideally the same day and time so your levels stay steady.
Before you inject: use a new pen needle every time. Check the pen and needle for damage, and that the liquid is clear and colourless to slightly yellow. Prime the pen before each injection, as shown in the leaflet.
Where: your stomach (at least 5cm from your belly button), upper thighs, or the outer part of your upper arms. Avoid veins and muscle, and change the spot each week to reduce irritation. See the images below to help with choosing an injection site.
After: put each used needle in a sharps bin. After your fourth dose, or 30 days after first use (whichever comes first), put the pen in your sharps bin, even if some liquid is left.
For more information, read our step-by-step guide for using the Mounjaro pen for a full walkthrough of the injection process.
Mounjaro missed doses
If you miss a dose, take it as soon as you remember if you’re within four days of the missed dose. If it’s been more than four days, skip it and go back to your usual schedule. Never take two doses to make up for a missed dose. If you’ve missed several doses, speak to our clinicians, as you may need to restart on a lower dose.
Concerned about giving yourself an injection?
“It’s natural to feel apprehensive about injections. Our team are here to provide support and advice to guide you through the process as smoothly as possible.”
Dr James Paweleck – Medical Director
Storing your Mounjaro pen
When it arrives: put the pen straight in the fridge, (2 – 8°C)
Once opened: you can keep a pen in the fridge or at room temperature (up to 30 degrees C). Throw it away 30 days after first use, even if there is medicine left
Store the pen with the cap on and never with a needle attached
If it overheats or freezes: don’t use it and dispose of it instead
If you’re travelling with Mounjaro, put your pens in your hand luggage rather than your hold luggage because temperatures can fluctuate. If you’re travelling to somewhere hot, use a cooling case to keep the medication at the right temperature.
We recommend travelling with the box your medication originally came in. This will have your dispensing label attached. This is useful if someone needs to check it against your passport.
Check your destination’s rules on bringing medication with you to make travelling as easy as possible. Always check with your airline about what documents are required to travel with Mounjaro. Some airlines may require an official travel letter which we offer.
Mounjaro side effects
Like all medicines, Mounjaro can cause side effects. Most are mild and ease off in the first few weeks as your body adjusts.
Very Common side effects (may affect more than 1 in 10 people)
- Nausea
- Diarrhoea
- Vomiting
- Constipation
- Low blood sugar (mainly when taken with certain diabetes medications)
For practical ways to handle them, see our guide on Mounjaro side effects and how to overcome them.
Common side effects (may affect up to 1 in 10 people)
Some people may experience other side effects while using Mounjaro. These can include:
- Faster pulse
- Allergic skin reactions such as rash, itching or eczema
- Stomach pain
- Indigestion
- Bloating
- Burping or wind
- Heartburn or acid reflux
- Feeling tired
- Dizziness
- Low blood pressure
- Hair loss
- Irritation, itching or redness where the injection was taken
- Changes in blood test results – increased pancreatic enzymes
Uncommon side effects
Uncommon side effects include gallstones, increased calcitonin (a hormone involved in calcium regulation) levels, pain at the injection site, an inflamed gallbladder and changes in how food tastes.
Serious side effects from Mounjaro
Less commonly, Mounjaro can cause serious side effects such as:
- Pancreatitis – severe stomach pain that does not go away and may spread to your back
- Allergic reactions
- Gallbladder problems – pain in the upper right of your tummy, fever, or yellowing of your skin or eyes
- Severe dehydration from vomiting or diarrhoea, which can damage your kidneys
If you experience any of these symptoms, such as breathing difficulties, swelling of the throat, face, and mouth, fainting, or severe stomach and back pain, stop taking Mounjaro and seek medical help immediately or call 999.
This is not a full list of possible side effects. Always read the patient information leaflet before using Mounjaro so you understand the possible side effects, warnings and precautions. Please report any side effects to our clinical team and through the MHRA Yellow Card scheme.
Switching to and from Mounjaro
Can I switch between Mounjaro, Wegovy and Wegovy Tablets.
Yes, you can switch. Mounjaro and Wegovy work differently so our clinicians help you switch to the most appropriate dose, based on your current dose and how well you are tolerating the medication.
The same goes for switching to or from Wegovy tablets. Complete a consultation, and our team will help you safely switch treatments.
Switching from Wegovy injection to Mounjaro
| Wegovy dose | Mounjaro dose |
|---|---|
| 0.25mg | 2.5mg |
| 0.5mg | 2.5mg |
| 1mg | 5mg or 7.5mg |
| 1.7mg | 10mg or 12.5mg |
| 2.4mg | 15mg |
| 7.2mg | 15mg |
Switching from Mounjaro to Wegovy injection
| Mounjaro dose | Wegovy dose |
|---|---|
| 2.5mg | 0.5mg |
| 5mg | 1mg |
| 7.5mg | 1mg |
| 10mg | 1.7mg |
| 12.5mg | 1.7mg |
| 15mg | 2.4mg or 7.2mg |
Switching from Mounjaro to Wegovy pill
| Mounjaro dose | Wegovy pill dose |
|---|---|
| 2.5mg | 1.5mg |
| 5mg | 4mg |
| 7.5mg | 9mg |
| 10mg | 9mg |
| 12.5mg | 9mg |
| 15mg | 25mg |
Switching from Wegovy pill to Mounjaro
| Wegovy pill dose | Mounjaro dose |
|---|---|
| 1.5mg | 2.5mg |
| 4mg | 2.5mg |
| 9mg | 5mg |
| 25mg | 5mg |
Buying Mounjaro online
Buying Mounjaro with The Family Chemist takes four steps, and our team are here to help you at each stage.
- Start your free consultation. Complete a quick online questionnaire about your health, weight, medications and goals.
- Clinician review. Once you’ve chosen your treatment preference, our clinicians review your answers to ensure Mounjaro is safe and right for you. They may suggest an alternative treatment, if indicated.
- Delivered to your door. If your treatment is approved, we send it out quickly in discreet packaging.
- Ongoing Support. A quick check-in every month, plus Nutrable access for meal plans, recipes and nutritional coaching.
Sources
Tirzepatide Once Weekly for the Treatment of Obesity (2022) The New England Journal of Medicine [accessed 12th November 2026]
Mounjaro 2.5/5/7.5/10/12.5/15mg KwikPen solution for injection in pre-filled pen (2024) EMC: Patient Information Leaflet [accessed 12th November 2026]
Wegovy 0.25 mg, FlexTouch solution for injection in pre-filled pen, emc [accessed 12th November 2026]
Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity (2024) JAMA [accessed 12th November 2026]
MHRA authorised diabetes drug Mounjaro (tirzepatide) for weight management and weight loss (2023) GOV.UK. [accessed 12th November 2026]
Yellow Card: Making medicines and medical devices safer, Medicines and Healthcare products Regulatory Agency (MHRA) [accessed 12th November 2026]
Weight management injections, NHS England [accessed 12th November 2026]
Troubleshooting common Mounjaro® (tirzepatide) KwikPen® questions (2025) Eli Lilly and Company Ltd [accessed 12th November 2026]
FAQs
How long does Mounjaro take to work?
Many patients using Mounjaro weight loss injections notice changes within the first 2 to 4 weeks, with bigger changes occurring in 8 to 12 weeks as the dose is increased.
- Early on (2–4 weeks): your appetite drops and portion control improves.
- Progressive weight loss (8–12 weeks): you’ll usually see visible weight loss as your dosage increases.
- Longer term: In the main trial, average weight loss continued to increase up to week 72
- Dose escalation matters: Gradual increases help minimise side effects and improve long-term results.
- Additional benefits: improvements in waist size, blood pressure, cholesterol and insulin sensitivity.
Troubleshooting a Mounjaro Pen
Eli Lilly publishes troubleshooting guidance for the KwikPen. These are the three things patients ask us about most:
- Air bubbles are normal and don’t affect your dose.
- Room temperature isn’t needed. You don’t need to warm the pen first.
- A drop of liquid or blood after injecting is normal. Press gently with cotton wool
Can you get Mounjaro on the NHS?
Yes, but access is limited. Not every GP practice prescribes it because of availability and eligibility criteria.
The rollout is happening in phases over several years, with priority given to patients with the highest medical need.
In the first phase, you needed a BMI of 40 or above. Since June 2026, this has been extended to people with a BMI of 35 to 39.9. In both cases you also need at least 4 of the following (lower BMI thresholds apply for some ethnic backgrounds):
- High blood pressure
- High cholesterol or abnormal blood fats
- Obstructive sleep apnoea
- Heart or cardiovascular disease
- Type 2 diabetes
Many people won’t qualify on the NHS yet. That’s why some choose to buy Mounjaro privately if they’d rather start sooner.
Has Mounjaro been clinically tested?
Yes. The SURMOUNT-1 trial is the main evidence for how well Mounjaro works. In the trial, adults with obesity (or who were overweight but did not have diabetes) lost a significant amount of weight when they took tirzepatide alongside diet and lifestyle changes.
The trial also helped confirm its safety profile. Mounjaro isn’t suitable for everyone, so use it only after a clinical assessment.
Can Mounjaro cause low blood sugar?
Wegovy, Ozempic and Rybelsus all contain the same active ingredient, semaglutide, but they’re licensed for different things. Wegovy is the only one licensed in the UK for weight loss.
- Wegovy is a weekly injection, licensed for weight management
- Ozempic is also a weekly semaglutide injection, but it’s licensed to treat type 2 diabetes
- Rybelsus is semaglutide in a daily tablet, again licensed for type 2 diabetes
If you’d prefer a tablet, the licensed oral option is Wegovy tablets, which use semaglutide and are approved for weight loss.
Does Mounjaro affect the contraceptive pill or HRT?
Mounjaro can affect how well some oral medications are absorbed, because it slows down how quickly your stomach empties.
This includes the contraceptive pill and oral HRT. Our guide has more detail on how weight loss injections can affect contraception.
Oral contraceptive pills: Mounjaro may make them less effective, especially when you first start and after each dose increase. Use a barrier method like condoms for 4 weeks after starting and for 4 weeks after each dose increase, or consider a non-oral method.
Oral HRT: Mounjaro may also affect absorption. Tell your GP or HRT prescriber that you’re starting Mounjaro, so that they can advise on monitoring or alternatives. Get medical advice if menopausal symptoms come back, or you notice breakthrough bleeding.
These things matter most in the first 4 weeks after you start, and after each dose increase
When is the best time to take Mounjaro?
You can take Mounjaro at any time of day, with or without food. The same day each week is the only rule. Pick one that fits your routine and set a phone reminder.
Can you change your Mounjaro injection day?
Yes, you can – but leave at least 3 days (72 hours) between doses. Once you’ve chosen your new injection day, continue taking Mounjaro on that day, once a week.
Try not to change your injection day too often, as this can affect how effective the treatment is. Sticking to a regular weekly routine helps the Mounjaro pen deliver consistent results and helps you stay on track with your weight loss goals.
How long do I have to stay on Mounjaro injections?
How long you use Mounjaro injections depends on your goals, how well it works for you and side effects you experience. We’ll review this with you as you go.
Some patients may need to stay on Mounjaro for longer to help maintain their results. Research from the SURMOUNT-4 trial found that people who stayed on the Mounjaro weight loss injection were more likely to maintain their results and keep losing weight, while those who stopped treatment were more likely to regain weight.
Our clinicians will monitor your progress and adjust your dose as needed.
What happens when you stop taking Mounjaro?
When you stop taking Mounjaro, your appetite may return, and you may regain some weight. It doesn’t happen the same way for everyone, though.
Research from the SURMOUNT-4 trial found that people who stopped treatment were more likely to regain weight than those who carried on. In a later analysis, 82% of people who stopped regained at least 25% of the weight they’d lost within a year, and about 1 in 4 regained 75% or more.
Many patients maintain their new weight by sticking with the habits they’ve built throughout treatment: balanced meals, sensible portions, and regular activity.
Our guide on stopping Mounjaro safely explains how to do it well, and our clinicians can help you decide when and how to stop.
Do you gain weight back after stopping Mounjaro?
Not always. Some people may regain weight after stopping Mounjaro injections, but it doesn’t happen the same way for everyone.
The SURMOUNT-4 data shows that those who stopped treatment are more likely to regain some weight. However, some people maintained their new weight through lifestyle changes, including calorie control and regular physical activity.
Mounjaro can support weight loss, but long-term weight loss usually depends on maintaining lifestyle changes after treatment stops.
What is the Mounjaro maintenance dose?
The maintenance dose is the dose you stay on long term to keep the weight off, usually 5 mg, 10 mg or 15 mg.
The right dose depends on your progress, your side effects and how well you tolerate the treatment. Plenty of people get steady results on a lower or middle dose and prefer to stay there.
If you’re weighing this up, our guide on whether to stick to your Mounjaro dose or move up may help, and you can read more about maintenance therapy too. Our clinicians will help you find what works for you.
Mounjaro vs Wegovy
Mounjaro and Wegovy are both weekly weight-loss injections that lower your appetite and support long-term weight loss. The main difference is the active ingredient and how it works.
Mounjaro contains tirzepatide, which works on two hormones (GLP-1 and GIP). Wegovy contains semaglutide, which works on GLP-1 only. Both are effective, though in a head-to-head trial people on Mounjaro lost more weight on average (20.2% vs 13.6% at 72 weeks).
The right choice depends on your goals and how well you respond to treatment. Our clinicians will help you decide, and you can read a more detailed comparison about Mounjaro vs Wegovy.
What are the alternatives to Mounjaro?
There are several alternatives to Mounjaro for weight management, each using different active ingredients and mechanisms to support weight loss. The options below are commonly prescribed in the UK:
| Mounjaro | Wegovy | Liraglutide | Wegovy Tablets | Xenical | Orlistat | Alli | Mysimba | |
| Category | Injection | Injection | Injection | Tablet | Tablet | Tablet | Tablet | Tablet |
| Active Ingredient(s) | Tirzepatide | Semaglutide | Liraglutide | Semaglutide | Orlistat | Orlistat | Orlistat | Bupropion and Naltrexone hydrochloride |
| Mode of Action | GLP-1 receptor agonist and GIP mimetic | GLP-1 receptor agonist | GLP-1 receptor agonist | GLP-1 receptor agonist | Lipase inhibitor | Lipase inhibitor | Lipase inhibitor | Multimodal action |
| Administration | Once weekly | Once weekly | Once daily | Once daily | With meals | With meals | With meals | With meals |
| Dosage | Starting at 2.5mg, up to 15mg | Starting at 0.25mg up to 7.2mg | Starting at 0.6mg up to 3mg | Starting at 1.5mg up to 25mg | One up to three times a day | One up to three times a day | 60mg up to three times a day | One to four tablets a day |
| Weight Loss % | Up to 21% to 22% | About 21% | About 5% to 10% | About 14% to 20% | About 5% to 10% | About 5% to 10% | About 5% | About 5% to 10% |
| Common Side Effects | Nausea, indigestion, diarrhoea, vomiting, constipation, stomach pain | Nausea, indigestion, diarrhoea, vomiting, constipation, stomach pain | Nausea, hypoglycaemia, diarrhoea, constipation, headache, decreased appetite | Nausea, indigestion, diarrhoea, vomiting, constipation, stomach pain | Oily spotting, gas with discharge, faecal urgency, fatty/oily stool | Similar to Xenical: Oily spotting, gas, faecal urgency | Similar to Xenical but may be milder due to lower dose | Nausea, constipation, headache, dry mouth, dizziness |
| Manufacturer | Eli Lilly | Novo Nordisk | Generic | Novo Nordisk | Cheplapharm Arzneimittel GmbH | Generic | Not specified | Not specified |
To explore weight-loss treatments, visit our weight loss injections page and begin your medically supervised weight-management journey with guidance from our prescribing team.
Where should you buy Mounjaro?
Buy Mounjaro only from a regulated UK pharmacy or an approved healthcare provider such as The Family Chemist.
Medically
reviewed by
Last reviewed: 12th November 2026
Meet our
medical professionals
Aaliyah Nelson
Nutritional Coaching
BSc (Hons) Nutrition: 47988
Standards first
always
