Mounjaro (tirzepatide) injections

What is Mounjaro?

Mounjaro weight loss injections are designed to help you achieve long-term, sustainable weight loss by reducing your appetite and making you feel full for longer, even as you eat less. If lifestyle changes alone haven’t worked, this treatment can be a great way to give you a helping hand.

Everyone starts on the lowest 2.5mg dose. If you see the results you want on that dose, there’s no need to change anything – you can stay on 2.5mg for as long as you like. However, you can also gradually increase your dose every 4 weeks until you reach a level of weight loss, and a maintenance dose, you’re happy with.

Each pen contains 4 doses, with one dose taken every week. You inject at home, meaning there’s no need to visit your local healthcare facility. This gives you greater control over your weight loss journey, allowing you to build a routine that works for you.

How does Mounjaro work?

Mounjaro doesn’t burn fat. Instead, it helps you stick to a weight loss plan by removing barriers that previously got in your way.

Unlike other weight loss injections, the active ingredient, tirzepatide, works by mimicking not one, but two natural hormones that appear in your body: GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide). This is why it’s known as a dual action agonist.

Once Mounjaro starts mimicking these hormones, it can help you lose weight in 3 main ways:

1. Cutting down on ‘food noise’: weight loss injections like Mounjaro are known for helping with ‘food noise’ – that feeling where food dominates your thoughts, like constant background chatter. By copying the hormones that send signals to your brain telling you you’re full, Mounjaro can make it easier to manage emotional eating and portion control.

2. Making you feel full for longer: Mounjaro slows down how fast your stomach digests food. This means you end up feeling fuller for longer, helping reduce the urge to snack between meals.

3. Regulating your blood sugar: tirzepatide was originally produced to help with diabetes and blood sugar levels. By stabilising your blood sugar, it can prevent you experiencing hunger spikes, again making it easier to manage your caloric intake.

How much weight can I lose on Mounjaro?

Clinical studies have found that, on average, Mounjaro can help people lose 22.5% of their starting weight over a 72-week period.

However, there are a number of factors that’ll determine how much you lose:

• your starting weight
• your target weight
• your diet
• your level of physical activity
• any underlying health conditions you might have
• your chosen dose
• how consistent you are with your treatment

How long do I need to stay on Mounjaro?

“There’s no set amount of time you need to stay on Mounjaro. For example, you may choose to stop your treatment once you’ve hit your target weight. Or, you could choose to stay on your maintenance dose long-term, after agreeing with your clinician it’s the right option for your body. The choice is up to you. We’re here to help you make a decision that’s healthy, sustainable, and tailored to your needs.”

Ayesha Bashir, weight loss expert

Benefits of Mounjaro beyond weight loss

Weight loss isn’t the only benefit of using Mounjaro. While there are still ongoing clinical trials to determine the full scope of Mounjaro’s benefits, it’s thought that the treatment can potentially help with:

• type 2 diabetes
• sleep apnoea
• heart failure
• kidney problems
• liver issues
• conditions like dementia and Alzheimer’s
• alcohol abuse
• nicotine addiction
• colon cancer
• polycystic ovary syndrome (PCOS)

This isn’t to mention ways weight loss can improve your personal confidence and mental health, with the benefits spreading to every area of your life.

Am I eligible for Mounjaro injections?

The eligibility criteria for Mounjaro depends on where you’re getting your treatment from.

To get Mounjaro with myWeightLoss, you need to:

• be 18 and over
• have a BMI of 30 or above, or a BMI of 27 and above alongside other weight-related health conditions, like type 2 diabetes

Our clinicians will also review your medical history and current medication to make sure it’s safe for you to take Mounjaro.

You can calculate your BMI using our calculator below:

Mounjaro on the NHS

It is possible to get Mounjaro on the NHS. However, you’ll need to meet a stricter set of criteria:

• a BMI of 35 or more, or 32.5 or more if you’re of Asian, Chinese, Middle Eastern, Black African or African-Caribbean origin
• a BMI of 30 to 34.9, or 27.5 to 32.4 if you’re of Asian, Chinese, Middle Eastern, Black African or African-Caribbean origin, and you meet other criteria to be treated by a specialist weight management service

Cost of Mounjaro

The cost of your Mounjaro weight loss injections depends on the dose you’re taking. There are currently 6 doses of Mounjaro, from 2.5mg to 15mg, with the price rising alongside the strength of the dose.

With myWeightLoss the price is as follows:

This price includes your consultation, your pen, delivery costs, and ongoing support and guidance from weight loss experts as you continue your journey.

Ordering Mounjaro with myWeightLoss

1. Online consultation: by filling out a short questionnaire, we can get to know you and your health, allowing the clinicians at myBMI to make the right decision for your needs. As part of your consultation, you’ll need to submit photos to confirm your identity and weight. But don’t worry – these will only be viewed by your clinician.

2. Clinical review: once you’ve submitted your consultation, it will be reviewed by a specialist weight loss expert. This clinician will carefully assess whether the treatment is right for you.

3. Delivery: if approved, your medication will be delivered in discreet packaging, using our tracked and signed-for service.

Ongoing support with myWeightLoss

Our service doesn’t end once your pen has been delivered. Through our partner pharmacy myBMI you’ll have:

• access to our patient support group
• regular reviews and ongoing advice from your prescriber
• resources to help you manage diet, exercise, and mindset
• side effects advice and treatment

Mounjaro dosing schedule explained

There are currently 6 available doses of Mounjaro, starting at 2.5mg up to a maximum dose of 15mg.

You start on the lowest dose and, if needed, gradually increase the strength over time in a process called titration. You have to be on a dose for at least 4 weeks before moving onto the next one, under supervision by a clinician.

“This gradual approach to titration is important, as it allows your body to get used to the treatment, helping to reduce the risk of side effects. It also means you can slowly find the right maintenance dose for long-term weight management.”

Ayesha Bashir, weight loss expert

Below is an example of a Mounjaro dosing schedule. However, your own dosing schedule will depend on how you react to the treatment, your target weight loss, and what your clinician agrees is best for your body.

Do you have to start at the lowest dose of Mounjaro?

Yes, everyone has to start on the lowest 2.5mg dose of Mounjaro. This is so your body has a chance to get used to the medication, reducing the likelihood of you experiencing side effects. Once you’ve been on 2.5mg for 4 weeks, you can discuss with your clinician whether you should increase your dose to the next strength.

Do you have to increase your dose of Mounjaro?

“No, you don’t have to increase your dose if you don’t want to. If you’re happy with your level of weight loss, you can stay at that dose as your maintenance dose. And if you’re struggling with side effects at your current dose, you can even return to a lower dose.

“Everybody responds to the treatment in different ways. It’s for you and your clinician to decide the right Mounjaro dosing schedule for your body.

“If you do want to increase your dose, all you need to do is request your next dose from myWeightLoss after at least 4 weeks on your current dose.”

Ayesha Bashir, weight loss expert

How to inject Mounjaro

For the best results, you should try and inject Mounjaro at the same time every week.

1. Pick your injection site. You can inject into your stomach (two inches away from your belly button) or thigh. You can also inject into your upper arm, but only if someone does it for you. You should rotate your injection sites each week to minimise skin irritation.

2. Check your pen isn’t damaged, the medication isn’t frozen, and the liquid isn’t cloudy. If you notice any issues with your pen, do not use it.

3. Wash your hands to reduce the chance of infection when injecting.

4. Attach the needle. You must always use a new needle every time you inject, even when using the same pen. Remove the cap, wipe the inner seal with a swab, push the needle in and twist until it’s tight, and pull off the inner and outer shields (keeping the outer shield for later).

5. Turn the dose knob until you hear two clicks and check that the extended line in the dose window aligns with the dose indicator.

6. Hold the pen upright to collect air bubbles at the top.

7. Push the dose knob until it stops, and count to 5. This should release some medicine.

8. Your dose window should now be showing ‘0’.

9. Turn the dose knob on your pen until it stops and the dose window shows ‘1’.

10. Insert the needle into your skin, push the dose knob until it stops and count to 5.

11. Once you’ve counted to 5, pull the needle out of your skin. The dose window should be showing ‘0’. If there’s any blood at the injection site, press on the site with a cotton ball.

12. Place the outer needle shield back on the pen and unscrew the needle. Put it into a sharps bin.

You should always read the instructions for use before injecting Mounjaro.

You can find out more about injecting Mounjaro with our partners at myBMI.

What happens if you miss a dose?

If you miss a dose of Mounjaro, you should take the missed dose as soon as possible, as long as it’s within 4 days of when you were meant to take it.

If more than 4 days have passed, you should skip the missed dose and take your next dose as normal.

You should never take 2 doses of Mounjaro within 3 days of each other.

What will my treatment look like?

As you start your journey, you may notice that the Mounjaro KwikPen that you receive from our partner pharmacy may vary across your first few orders. This is because the manufacturer, Eli Lilly, has introduced a new, modified version of the pen.

Both versions of the pen work and are used in the exact same way. The only difference is the plunger within the cartridge, to help you follow how much treatment is left.

In the modified pen you’ll notice:

• On an unused pen, the plunger is further down the cartridge.
• A new piece has been added, extending the plunger to assist with dosing.
• A clearer way to indicate that the pen has been finished after the fourth dose, as the plunger will be nearer the end of the pen.

With an older model of the pen, after your final dose there may be surplus treatment within the treatment window. However, this should not be used as treatment.

Temporarily, orders will be sent out with either an original or updated KwikPen. This is only during the transition period and depends on pharmacy stock. Eventually, all pens dispensed will be the newer, modified version.

How to store your Mounjaro pen

Before you’ve opened your pen, it needs to be stored in the fridge (between 2°C and 8°C). Try storing it in the fridge door to avoid it becoming frozen.

After you’ve first used your pen, it can be kept at room temperature for up to 30 days. This is long enough to cover the full dosing schedule of one pen.

How to dispose of your pen

Once you have used all 4 doses in your pen, you can throw it away in your normal rubbish bin. However, the needle must be removed and disposed of in a sharps bin.

Getting the most from your Mounjaro treatment

To get the most from your Mounjaro treatment, the injections should be combined with a balanced diet and regular physical activity.

Food

Taking Mounjaro is a great time to reevaluate your eating habits, and start putting some positive changes in place.

When it comes to what you eat, focus on balanced meals containing lean proteins (like chicken breast), high-fibre fruit and veg (think broccoli and leafy greens), complex carbs (like brown rice and chickpeas) and healthy fats (including avocado and olive oil).

When it comes to how you eat, there are a number of changes you can consider, like:

• regular mealtimes to help your build routine and avoid snacking
• smaller portions to avoid bloating and nausea
• lighter, plainer meals on your injection days to help minimise side effects

Hydration is also a hugely important part of your journey on Mounjaro. It’s better to regularly drink a little, rather than glugging large amounts at once, to avoid discomfort.

Reducing your alcohol intake, meanwhile, can help avoid making any side effects worse, while cutting out empty calories that may interfere with your weight loss goals.

Our partners at myBMI can help you with your Mounjaro diet plan.

Exercise

Like every aspect of your Mounjaro journey, your exercise plan is personal to you. And it doesn’t have to mean going to the gym. It’s better to start slow, build sustainable habits, and find what activities work best for you, then to rush into a schedule that you can’t keep up with.

Any movement counts, whether that’s a short walk after dinner (which has the added benefit of helping with digestion), daily stretching exercises, or even doing a bit of gardening.

Get more guidance on creating the best weight loss programme with myBMI.

Why am I not losing weight on Mounjaro?

If you’re not losing weight on Mounjaro, don’t panic. There are a number of things it could be, including:

• It’s too early in your journey: while Mounjaro starts working straight away, weight loss isn’t instant. It can take a few weeks for your reduced appetite to turn into noticeable weight loss.
• Your weight loss has plateaued: depending on your starting weight, you may have experienced a significant amount of weight loss early on, only to see it slow down over time. This doesn’t mean the treatment is no longer working, just that you may need to consider some further lifestyle or dosage changes as your body adjusts to the medication.
• Your dose is too low: some people find that significant weight loss doesn’t happen until they’re on the higher doses of Mounjaro. Speak to your clinician to see if a higher dose is the right option for you.
• You need to reexamine your diet plan: Mounjaro will only work effectively alongside healthy eating habits. If you aren’t in calorie deficit, where you’re eating fewer calories then you’re burning, you likely won’t be able to achieve the results you want.
• It’s not the right medication for your body: if sustained use of Mounjaro, combined with consistent lifestyle changes, hasn’t led to the results you want, you could speak to your clinician about other weight loss medications.

Most common Mounjaro side effects

Like any medication, you may experience some side effects when taking Mounjaro, typically when starting the treatment, and when upping your dose. For most people, they go away on their own, as your body adjusts to the medication. And our partners at myBMI will be there every step of the way to help you navigate these changes.

Below are the most common side effects of Mounjaro, affecting more than 1 in 10 people who take the treatment.

Nausea and vomiting

One of the ways Mounjaro helps with weight loss is by slowing down how quickly food leaves your stomach. This can cause you to experience nausea, and potentially vomiting, during the first few weeks of treatment, and when you increase your dose. This should go away on its own over time, without the need for you to stop your treatment.

Tips for managing your nausea and vomiting include:

• Eating smaller meals, more regularly: by avoiding larger meals, you can give you body the time it needs to digest your food.
• Be selective with what you eat: stick to blander foods, like rice and crackers, while avoiding fatty and processed foods.
• Stay hydrated: like with so many Mounjaro side effects, stay hydrated by regularly sipping water, can help you manage your nausea. It’s especially important if you’ve actually been sick. Other drinks, like ginger teas, can also help settle your stomach.

Diarrhoea

Another side effect of Mounjaro slowing how your stomach empties is diarrhoea.

If you are dealing with diarrhoea, it’s important to stay hydrated. This can include taking over-the-counter rehydration sachets, so you get the added benefit of topping up your electrolytes.

As with nausea, bland foods that are easier to digest can also help, while try to avoid things like coffee and alcohol that can act as natural laxatives.

Constipation

You may end up having the opposite problem to diarrhoea. If you experience constipation, it’s a good idea to try and pack your diet full of high-fibre fruits and vegetables.

Staying hydrated is important, as increased water absorption from your gut is one of the reasons that can cause this side effect.

Regular movement can also keep your movement regular, so try building physical activity into your daily routine.

Stomach pain

Stomach pain while taking Mounjaro can include indigestion, bloating, cramping, and gas. As with the other common side effects, eating smaller meals more regularly, watching what you eat, and trying to do some physical activity each day can help.

Other common side effects

Other common side effects of Mounjaro include:

• burping
• reflux or heartburn
• hair loss
• feeling tired
• injection site reactions

For more information on Mounjaro side effects, visit our partners at myBMI.

When to seek medical help

You should seek urgent medical assistance if you experience:

• gallbladder problems
• severe stomach or back pain that doesn’t go away, alongside nausea or vomiting, as this could be pancreatitis
• signs of anaphylaxis (difficulty breathing, or swelling in your face, tongue or throat

You should talk to your doctor if your side effects are affecting your day-to-day life or are not getting better over time.

Who shouldn’t take Mounjaro?

You shouldn't take Mounjaro if you:

• are under 18
• are pregnant or breastfeeding
• are allergic to any of the ingredients
• have a personal or family history of medullary thyroid carcinoma (MTC)
• have Multiple Endocrine Neoplasia syndrome type 2 (MEN 2)

You should speak to your clinician before taking Mounjaro if:

• you've previously had pancreatitis
• you have a problem with your eyes (diabetic retinopathy or macular oedema)
• you're using another diabetes medication or insulin to treat your condition

You should also tell your clinician about any medication you are taking, as they can advise you on any interactions with your treatment.

Alternatives to Mounjaro

If Mounjaro isn’t right for you, you could consider:

• Wegovy: an alternative weight loss injection, containing the active ingredient semaglutide, which offers average weight loss of 21%.
• Saxenda: another weight loss injection, containing liraglutide, which offers average weight loss of around 10%.

There are also weight loss pills, including Mysimba and Orlistat, if you’d prefer a non-injectable treatment.

Mounjaro vs Wegovy

Mounjaro and Wegovy are the two main weight loss injections currently available in the UK. They work in similar ways, reducing your appetite while making you feel fuller for longer.

While Mounjaro has clinically shown higher levels of weight loss, Wegovy is more affordable.

To help you make a decision, we’ve compared the two below:

Sources

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