Weekly treatment designed to fit your routine

Mounjaro® is a once-weekly injection containing tirzepatide. If prescribed, it can be taken on the same day each week alongside healthy eating and increased physical activity.

Simple.
Compliant.
Patient friendly.

Clinical Trial Results

Up to 20.9%

Average body weight reduction observed in a 72-week clinical trial of adults with obesity or overweight and at least one weight-related condition.*

*Clinical trial results are averages from specific study populations. Individual outcomes may vary and treatment should always be used as prescribed.

What Is Mounjaro® Injection?

Mounjaro® injection is a Prescription Only Medicine (POM) containing tirzepatide. It is a once-weekly prescription treatment used to help eligible adults manage weight alongside a reduced-calorie diet and increased physical activity, and it is also prescribed for the treatment of type 2 diabetes. For UK adults living with obesity or overweight who want a clinically prescribed, medically supervised weight-management option, this guide explains what Mounjaro is, how it works, who may be eligible, what results have been seen in clinical trials, how it is taken, and the key safety points to understand before starting treatment.

Tirzepatide works with the body's natural hormone systems involved in appetite, food intake and blood sugar regulation. Alongside helping some people feel fuller for longer and reducing hunger, this effect may also support blood sugar control and help lower metabolic risks, which can make long-term lifestyle changes easier to maintain under professional supervision.

However, responses vary from person to person and treatment outcomes vary.

Before you can be prescribed Mounjaro, a qualified healthcare professional will review your medical history, current health, body mass index (BMI), any existing medical conditions, and the medicines you are taking. This article also covers dosage and administration, possible side effects, lifestyle recommendations, and why an online clinical consultation is important to make sure treatment is appropriate and safe for you.

But not everyone can take Mounjaro and that's why it is not available over the counter. A clinical assessment is always required before treatment can commence.

The Medicines and Healthcare products Regulatory Agency (MHRA) authorised Mounjaro for weight management in eligible adults in the UK in 2023. You can read more about the approval here.

Why Is Mounjaro Prescribed?

Managing your weight can be challenging for many people. Changes in appetite and feelings of fullness can make it more difficult for some people to maintain a reduced-calorie eating plan over time.

Mounjaro, when prescribed appropriately, can help eligible adults to support a wider weight management programme:

• May help you feel fuller after eating.
• May help reduce appetite.
• May support portion management.
• May help support healthier eating habits.
• May help support long-term lifestyle changes when combined with diet and physical activity.

Mounjaro is designed to support your weight loss journey, not replace healthy habits. It should be used with a balanced diet, regular exercise, and advice from your healthcare professional.

How Does Mounjaro Work?

Mounjaro contains tirzepatide, which works by activating GLP-1 and GIP, two naturally occurring hormone receptors in the body:

• GIP (Glucose-dependent Insulinotropic Polypeptide) receptor
• GLP-1 (Glucagon-like Peptide-1) receptor

These hormones are released after eating and play a role in regulating appetite, digestion, feelings of fullness and blood sugar.

By acting on both hormone pathways, Mounjaro may help:

• Reduce feelings of hunger
• Increase feelings of fullness after meals
• Slow the rate at which food leaves the stomach
• Support adherence to a reduced-calorie diet

GIP is involved in regulating energy balance and metabolism, although its effects may vary between individuals.

Because every person's body responds differently, the effects of treatment can vary. Some people notice changes sooner than others, while some may require dose adjustments under medical supervision. Using Mounjaro as prescribed is important to support treatment goals.

Treatment should always be used alongside healthy eating, regular physical activity and ongoing clinical support where appropriate.

Already Using Another Weight Management Injection?

Do not switch to Mounjaro® if you are currently using another prescription weight management injection, such as semaglutide, unless directed by a healthcare professional.

The medicines may be used for similar purposes but they have different active ingredients and act in different ways. The dose of one medicine cannot be directly compared to that of another. Changing treatment requires careful clinical assessment.

During your online consultation, your prescriber will ask you about:

• Your weight management medication (current/past)
• The dosage you are on
• How long you have been using it
• Any side effects you've had
• Your progress to date
• Your medical history and current medications

From this information, they will determine if Mounjaro may be appropriate and, if so, the most appropriate starting dose.

Do not stop your current treatment or change medicines without speaking to a healthcare professional first.

Directions for Use

Mounjaro® is a once-weekly injection and should always be used exactly as directed by your healthcare professional.

Your prescriber will determine the right dosing schedule for you. Treatment is usually started at a low dose and may be increased gradually, if appropriate. This gradual process allows your body to get used to the medication and may reduce the risk of gastrointestinal side effects.

Taking your weekly injection

To help you get the most from your treatment:

• Inject Mounjaro once a week on the same day each week where possible. You can change your injection day if at least 72 hours have passed since your last dose.
• Choose a time of day that fits your routine.
• The injection can be taken with or without food.
• Follow the instructions provided with your KwikPen® and your prescriber's Mounjaro dosage schedule.
• Mounjaro dosage commonly starts at 2.5 mg and is then titrated gradually by healthcare providers to minimise side effects.
• Never use more than the prescribed dose.

Where to inject

Mounjaro is given as an injection under the skin (subcutaneous). Common options for the injection site are:

• Abdomen (area of the stomach)
• Front of thigh
• Upper arm (if injection is being given by someone else)

It's best to change injection sites regularly to help reduce skin irritation.

If you forget a dose

If you forget to take a dose, follow the advice given in the Patient Information Leaflet or the advice given by your healthcare professional. A missed dose should usually be taken within 96 hours, following the Patient Information Leaflet or your prescriber's advice.

Don't take extra doses or inject more than your doctor ordered to make up for a missed dose.

If you are not sure what to do, contact your prescriber or pharmacist, or speak to your doctor, before you take your next injection.

Storage

To help maintain the quality of the medicine:

• Store unused pens in a refrigerator between 2°C and 8°C.
• Do not freeze the medicine.
• Keep the pen in its original packaging to protect it from light.
• Follow the storage instructions provided with your pen once it has been opened.

Always check the expiry date before use.

Safe disposal

Used needles should be placed in an approved sharps container.

Never dispose of loose needles in household waste and never share your injection pen with another person, even if the needle has been changed.

For complete prescribing information, including storage, dosing and administration guidance, refer to the Mounjaro Summary of Product Characteristics (SmPC).

Why Lifestyle Changes Still Matter

Mounjaro is designed to help you manage your weight. But it's not a substitute for good lifestyle habits.

Treatment is intended to be used alongside a reduced-calorie diet and regular physical activity.

Sustainable lifestyle changes may help support long-term healthy habits.

Some simple ways to support your weight management plan include:

Eat a balanced diet

Focus on meals that include:

• Lean sources of protein
• Vegetables and fruit
• Wholegrains
• Healthy fats in moderation

Eating regular meals and paying attention to portion sizes may also help you stay on track.

Stay physically active

Physical activity doesn't need to be intense to make a difference.

Activities such as:

• Walking
• Swimming
• Cycling
• Strength training
• Low-impact exercise

can all form part of a healthy routine. Choose activities you enjoy and can maintain over time.

Prioritise sleep

Poor sleep may affect appetite, food choices and energy levels. Aim for a regular sleep routine whenever possible.

Stay hydrated

Staying hydrated is important during treatment, particularly if you experience vomiting or diarrhoea.

Attend regular reviews

Your prescriber may recommend follow-up appointments to monitor your progress, discuss any side effects and review whether treatment remains appropriate.

Remember, everyone's journey is different. Lifestyle changes and medicine work together, and progress can vary from person to person.

The NHS also recommends that weight management medicines are used as part of a wider programme that includes healthy eating, physical activity and behavioural support where appropriate.

Why an Online Consultation Is Required

Mounjaro® is a Prescription Only Medicine (POM) and must be prescribed by a suitably qualified healthcare professional.

An online consultation is a way of ensuring treatment is prescribed safely and only when clinically appropriate.

Your assessment will include answering questions about your:

• Weight and Height
• Body Mass Index (BMI)
• History of Present Illness
• Current medications
• Allergy issues
• Prior weight management treatments
• Pregnancy or Breastfeeding status (if applicable)
• Pre-existing conditions

In the UK, a qualified prescriber will go over your answers and determine if Mounjaro is right for you.

You may be contacted for more information before a prescribing decision is made.

Why is this important?

Weight management medicines are not suitable for everyone.

Some medical conditions, medicines or personal circumstances may affect whether Mounjaro can be prescribed safely.

A clinical assessment helps ensure that:

• The treatment is appropriate for your individual needs.
• Potential risks and benefits have been carefully considered.
• You receive the correct starting dose if treatment is prescribed.
• You understand how to use the medicine safely.

If Mounjaro is not considered suitable, your prescriber may discuss alternative approaches to weight management that better match your clinical needs.

Ongoing Support During Treatment

Starting treatment is only one part of your weight management journey, and your clinical team may review progress and support treatment over time.

Depending on your provider, ongoing clinical support may include:

• Reviews of your progress
• Dose adjustments where appropriate
• Advice on managing side effects
• Guidance on healthy eating and physical activity
• Assessments to ensure treatment remains suitable

Regular reviews allow your healthcare professional to monitor your response to treatment and answer any questions you may have throughout your weight loss journey.

Is Mounjaro® Right for You?

Mounjaro® is prescribed to eligible adults to help manage their weight. However, as with all prescription medicines, it may not be suitable for everyone.

Before Mounjaro is prescribed, a healthcare provider will review your health history and current medications to determine if treatment is appropriate for you.

Your online consultation is an important part of this process and helps to ensure the safe use of the medicine.

You may be eligible if:

Mounjaro may be considered for adults who meet the licensed prescribing criteria in the UK. This generally includes adults living with:

• Obesity, typically with a Body Mass Index (BMI) of 30 kg/m² or above, or
• Overweight, typically with a BMI of 27 kg/m² or above, when accompanied by at least one weight-related health condition.

Examples of weight-related conditions may include:

• High blood pressure
• Type 2 diabetes
• High cholesterol
• Obstructive sleep apnoea
• Cardiovascular disease
• Other obesity-related health conditions

Your prescriber will also consider factors such as your ethnic background, overall health and medical history when assessing eligibility, as BMI thresholds may vary for some populations.

Meeting the BMI criteria alone does not automatically mean Mounjaro is suitable. Every prescription is based on an individual clinical assessment.

Who may not be suitable for Mounjaro?

There are situations where Mounjaro may not be recommended or where extra care is needed before treatment can begin.

You should tell your healthcare professional if you:

• Are pregnant or planning a pregnancy
• Are breastfeeding
• Have ever had pancreatitis
• Have severe stomach or digestive disorders
• Have significant kidney or liver problems
• Have gallbladder disease
• Have diabetic eye disease (diabetic retinopathy)
• Have a personal or family history of medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN2)
• Have experienced an allergic reaction to tirzepatide or any ingredient in Mounjaro

Your healthcare professional may recommend a different treatment if they believe another option would be more appropriate.

Always provide accurate information during your consultation so the safest prescribing decision can be made.

Potential Benefits of Treatment

When prescribed appropriately and used alongside healthy lifestyle changes, Mounjaro may support weight management in several ways.

The medicine works by helping to regulate appetite and feelings of fullness, which may make it easier for some people to follow a reduced-calorie eating plan.

Potential benefits may include:

Helping to Manage Appetite

Many people taking Mounjaro injection report feeling less hungry between meals. Reduced appetite may make it easier to manage food intake, although experiences vary.

Feeling Fuller for Longer

Mounjaro injections act on natural hormones involved in appetite regulation. Some people may notice they feel satisfied after eating smaller portions.

Supporting Long-Term Lifestyle Changes

Healthy habits such as balanced eating and regular physical activity remain essential.

For some people, treatment may help support these lifestyle changes by making it easier to maintain healthier routines.

Once-Weekly Dosing

Unlike medicines that require daily dosing, Mounjaro is taken once a week. Many people find that a consistent weekly schedule is easier to fit into their routine.

Regular Clinical Monitoring

Because treatment is prescribed and monitored by a healthcare professional, your progress, side effects and ongoing suitability can be reviewed throughout your treatment.

It is important to remember that individual responses vary. Some people may experience greater changes than others, while some may decide with their prescriber that another treatment approach is more suitable.

Possible Side Effects

Like all medicines, Mounjaro injections can cause side effects, although not everybody experiences them, and this safety overview covers the side effects of Mounjaro you may need to know about.

Many side effects are mild to moderate and are most common when treatment begins or when the dose is increased. They often improve as your body adjusts to the medicine.

If side effects are persistent, severe or causing concern, speak to your healthcare professional.

Common Side Effects

Some of the more commonly reported side effects include:

• Nausea
• Diarrhoea
• Vomiting
• Constipation
• Stomach pain
• Indigestion
• Reduced appetite
• Burping
• Bloating
• Tiredness
• Hair loss may affect up to 1 in 10 users

Your prescriber may recommend increasing your dose gradually to help reduce the likelihood of gastrointestinal side effects.

Tips that may help

Some people find it helpful to:

• Eat smaller meals
• Eat more slowly
• Avoid very rich or fatty foods
• Drink enough fluids throughout the day
• Continue taking the medicine exactly as prescribed unless advised otherwise

These suggestions may not work for everyone, but they can help some people manage common digestive symptoms.

Serious Side Effects – When to Seek Medical Advice

Serious side effects are less common but require prompt medical attention.

Seek urgent medical advice immediately if you experience:

Signs of Pancreatitis

• Severe abdominal pain that is persistent
• Pain spreading to your back
• Pain accompanied by nausea or vomiting

Severe Allergic Reaction

Symptoms may include:

• Swelling of the face, lips, tongue or throat
• Difficulty breathing
• Difficulty swallowing
• Severe rash or itching
• Feeling faint

This requires immediate emergency medical attention.

Severe Dehydration

Persistent vomiting or diarrhoea can lead to dehydration, particularly if fluid intake is reduced.

Seek medical advice if you are unable to keep fluids down or develop symptoms such as dizziness, confusion or reduced urination.

Warnings and Precautions

Before starting treatment, your healthcare professional will assess whether Mounjaro is appropriate for you.

Be sure to mention if you:

• Have kidney disease
• Have liver disease
• Have gallstones or gallbladder problems
• Have previously had pancreatitis
• Have diabetic eye disease
• Are taking medicines for diabetes, particularly insulin or sulfonylureas
• Take oral contraceptives
• Have severe gastrointestinal disease

Some medicines may require dose adjustments or closer monitoring while using Mounjaro.

Pregnancy and Breastfeeding

Mounjaro injection is not recommended during pregnancy.

If you become pregnant or are planning a pregnancy, tell your healthcare professional as soon as possible.

It is also not generally recommended while breastfeeding because it is not known whether tirzepatide passes into breast milk.

Driving and Using Machines

Mounjaro itself is not expected to affect your ability to drive.

However, if it is used alongside insulin or certain diabetes medicines, low blood sugar (hypoglycaemia) may occur, which can affect concentration and reaction times.

If this applies to you, discuss safe driving with your healthcare professional.

Safety Information

Always use Mounjaro exactly as prescribed.

Do not:

• Share your injection pen with another person.
• Change your dose without medical advice.
• Stop treatment suddenly without discussing it with your prescriber.
• Use the medicine after its expiry date.
• Use a pen that has been stored incorrectly or appears damaged.

For complete information about contraindications, precautions, interactions and administration instructions, refer to the official Mounjaro Summary of Product Characteristics (SmPC) published by the MHRA.

Oral Weight Management Medicines

Some people may be suitable for oral prescription medicines instead of injections. Your prescriber will discuss whether these are appropriate based on your medical history and treatment goals.

Lifestyle Support

For some individuals, structured lifestyle changes may be the most appropriate first step. This may include:

• Dietary advice
• Physical activity plans
• Behavioural support
• Ongoing clinical monitoring

NHS Weight Management Services

Depending on your circumstances, you may also be eligible for NHS-supported weight management programmes, which can provide a structured weight loss service. These services can include lifestyle support and, for some people, access to prescription medicines where clinically appropriate.

Frequently Asked Questions

Is Mounjaro® available without a prescription?

No. Mounjaro is a medicine that you can only get with a prescription in the UK. A doctor or a nurse has to decide if Mounjaro is right for you before you can take it.

How often do I use Mounjaro?

You take Mounjaro once a week on the same day every week if you can. Your doctor or nurse will tell you how to give yourself the injection and when to do it.

How does Mounjaro work?

Mounjaro has an ingredient called tirzepatide. Mounjaro for weight loss works by acting on GLP-1 and GIP pathways to help reduce appetite and support feelings of fullness. If you also make lifestyle changes, Mounjaro might help you manage your weight.

When might I notice changes?

Everyone is different so you might notice changes at different times. Some people feel less hungry straight away, while others might take longer to see changes in their weight. If you're wondering how much weight you may lose, results vary from person to person and depend on your treatment plan. It also depends on how well you stick to your treatment plan.

Do I still need to follow a healthy diet?

Yes. You should still eat food and not too much of it. You should also try to be more active. Mounjaro is meant to be used with a diet and exercise to help you manage your weight.

Can I exercise while using Mounjaro?

Yes, you can exercise while taking Mounjaro unless your doctor or nurse tells you not to. Regular exercise is actually a good idea because it can support weight loss and help you stay healthy.

What should I do if I miss a dose?

If you miss a dose of Mounjaro you should read the instructions that come with your medicine or talk to your doctor or nurse. Do not take a double dose to make up for the one you missed.

Can I switch from another weight management injection?

Maybe. You should talk to your doctor or nurse about it. They will decide if switching to Mounjaro is right for you and may need to review your current Mounjaro dose or the injection you are switching from before advising on the change.

Can I drink alcohol while taking Mounjaro?

Alcohol may worsen some side effects, such as nausea, in some people. If you're unsure, speak to your healthcare professional.

Is Mounjaro injection suitable during pregnancy?

No. Mounjaro is not recommended during pregnancy. If you are pregnant, planning a pregnancy or breastfeeding, tell your healthcare professional before starting treatment.

Can Mounjaro injections be taken with other medicines?

Mounjaro can interact with some medicines, so tell your prescriber about anything you take before starting treatment. They may review your current dose, other prescriptions, over-the-counter medicines, and supplements to check whether Mounjaro is suitable for you.

How should I store my injection pen?

You should keep your Mounjaro pen in the fridge between 2°C and 8°C. Do not use the pen after it expires.

Will Mounjaro work for everyone?

No. Individual responses vary. Treatment outcomes depend on many factors, including medical history, lifestyle changes, adherence to treatment, individual response to the medicine, and dose level, so average weight loss can differ from person to person.

Is Mounjaro a long-term treatment?

It depends on you. Your doctor or nurse will check on you regularly to see if you should keep taking Mounjaro. Many people stay on treatment long term with dose reviews, and healthcare providers typically titrate the dose over time to balance effectiveness and side effects. Not everyone needs the maximum dose to benefit, and the maximum maintenance dose is usually 15mg weekly.

Where can I find official information about Mounjaro?

You can read the official UK prescribing information in the MHRA Summary of Product Characteristics (SmPC).

Ready to Start Your Consultation?

If you're thinking about Mounjaro® for weight management, the first step is to complete a private online consultation.

Your answers will be reviewed by a qualified UK healthcare professional who will take into account your medical history, health and eligibility to make a decision about whether Mounjaro Injection or another weight loss medication is clinically appropriate for you.

If prescribed, your medicine will be dispensed by a registered UK pharmacy and you will receive clear guidance on how to use it safely.

Complete your online consultation today to find out whether Mounjaro Injection may be suitable for you.