Mounjaro is a once-weekly Tirzepatide injection recommended as a first-line treatment for weight loss by our medical experts at myBMI’s weight loss clinic.
Tirzepatide (also known as Mounjaro) is the latest GLP-1 receptor agonist to hit the market and it could mean big things for the future of weight loss medication.
Like other medications of this type, it works by interacting with your hunger hormones, reducing your appetite and helping you feel fuller for longer.
You’ll inject this medication yourself once a week, at a time that suits you, giving you control over your treatment and how it fits into your busy life.
Mounjaro is the brand name of the medication Tirzepatide when it is used as a type 2 diabetes treatment.
Semaglutide is known as Ozempic when it is used as a type 2 diabetes treatment and as Wegovy when it’s used for weight management, Liraglutide is known as Victoza when used for diabetes and Saxenda when used for weight loss.
At this point, we don’t know what brand name Tirzepatide will take if it is licensed as a weight loss treatment, but we do know that Mounjaro is only licensed to treat type 2 diabetes.
We understand that all these different medical names can be confusing, so here’s a handy table that breaks down the active ingredients available and the name of each medication.
Mounjaro is not licensed in the UK now, but if it becomes available in the UK, it will not be licensed as a weight-loss treatment under that name.
However, this doesn’t mean that Tirzepatide will not be licensed for weight loss under another brand name.
Other GLP-1 receptor agonists have followed a similar pattern during the licensing process, first being licensed for type 2 diabetes and then being licensed for weight loss a short time afterwards.
While Tirzepatide may be prescribed off-label to help certain patients reach their weight loss goals, this will only be done at the discretion of the prescriber and only when they are confident of the benefits this would have for their patient.
Tirzepatide works by interacting with the hormones created in your pancreas to help you manage your blood sugar — insulin and glucagon.
It helps to stimulate the production of insulin while slowing down the production of glucagon.
These changes in your hormone production will help you to feel fuller for longer, slow down the emptying of your stomach, and reduce your appetite, making it easier for you to stick to a calorie-controlled diet.
Reducing your calorie intake is one of the most important aspects of weight loss, and many patients have found that this helping hand with sticking to their diet has been invaluable to their progress.
Pairing Tirzepatide with a healthy, balanced diet and regular exercise can be a winning combination for patients looking to lose weight and reduce their risk of type 2 diabetes.
Yes, Tirzepatide is a GLP-1 receptor agonist, meaning it’s part of the same group of medications as Wegovy and Saxenda.
As they’re the same type of medications, these treatments all work similarly — by affecting your hunger hormones.
GLP-1 agonists have been around for a few years now, with Liraglutide (Saxenda) being available on the NHS and Semaglutide (Wegovy) following a similar path.
If the manufacturer of Tirzepatide decides to follow the same licensing route other GLP-1 receptor agonists have gone down.
In that case, we’ll probably find that it will be licensed as a type 2 diabetes treatment first, then licensed for weight loss.
This will happen in the US before the medication comes to the UK.
At the moment, it has been licensed for diabetes in the US under the brand name Mounjaro, so the process is off to the predicted start.
Unlike other, similar medications, Tirzepatide works as a GIP receptor agonist as well as a GLP-1 agonist.
This means that it works on another hormone that is created in your body to regulate your appetite, specifically one that relates to your insulin production.
GIP receptor agonists were created to be another treatment option for type 2 diabetes patients, much like GLP-1 agonists, and as these treatments work on slightly different hormones, they can work together successfully.
In the case of Mounjaro, this unique combination of GIP and GLP-1 agonists helps to reduce your appetite, slow gastric emptying so you’ll feel fuller for longer, increases your insulin secretion and reduces glucagon levels.
Tirzepatide comes in single-use pens that you’ll use to administer your injection once a week.
The first thing you’ll do is choose where to inject, and your prescriber can help you to make that decision if you need a hand.
You can choose between your stomach, your thigh, or the back of your upper arm.
You will need to inject in a different place every week, although you can inject in the same general area.
For example, you may choose to inject on the right side of your stomach one week and the left side the week after, or you may choose to alternate between injecting your stomach and thighs.
Make sure the pen is locked before removing the grey base cap and throwing it away with your household waste.
Press the clear base of the pen flat against the skin where you’d like to inject and then unlock the pen.
Finally, press the purple injection button on the other end of the pen and hold it down for 10 seconds.
You’ll hear one click to tell you your injection has started and another to tell you the injection is finished, if you’re unsure of the clicks, you’ll know the injection is complete when you can see the grey plunger.
When you’re done, put the used pen in a sharps bin so it can be collected by your local council and disposed of safely.
You will inject Tirzepatide once a week, on the same day, at a time that suits you.
You can take it at any time of day, so feel free to choose a time that’s right for you and your schedule.
If you need to change your injection to another day then that’s absolutely fine!
Just make sure that you leave at least three days between your injections and speak to your prescriber if you’re at all unsure of how to change days safely.
If you accidentally miss a dose, that’s okay too.
If you are within four days (or 96 hours) of your original injection time then just take your next dose as soon as you remember to.
If four days have passed since your original injection time, skip this week’s dose and take your next injection at your usual time — this will keep you from taking two doses within three days, which could lead to an overdose.
This is the lowest dose available for Mounjaro injections, and you’ll usually start by taking this for the first 4 weeks.
The main purpose of starting on the lowest dose is to avoid experiencing any severe side effects, so please don’t be disheartened if you don’t see much movement on the scales whilst you’re taking 2.5mg.
Some people do start to see some weight loss even on this lowest dose.
Taking 2.5mg injections weekly for the first month of treatment means that your body will be allowed to gradually get used to the medication before you titrate up to a higher dose.
From weeks 5-8, most people move onto a 5mg injection every week.
Although this still isn’t the therapeutic dose, remember that this is still a titration period to allow your body a chance to adjust to treatment.
You should take the 5mg dose weekly throughout your second month of treatment.
From week 9, you’ll be able to take a weekly dose of 7.5mg.
For most people, this is enough to start seeing results, and many people who take weekly injections for weight loss stay at this dosage for as long as they need to.
You shouldn’t ever take 7.5mg straight away without titrating up from a lower dose, as this could cause severe side effects.
The Sustain plan is suitable for people who have been taking a 7.5mg dose for a while and have either reached a plateau or stopped seeing as much success as expected.
The higher doses of Mounjaro are ideal for those who have seen success with their treatment so far but could benefit from a stronger dose as treatment continues.
Your prescriber will make the final decision about whether or not a surge plan would be appropriate for you, and if so, how long you should stay on it.
Like all medications, Tirzepatide and Mounjaro can have side effects, although you may not experience them for yourself.
The most common side effects of this medication include:
As you’ve probably noticed, the most common side effects of Tirzepatide are all to do with your digestive system.
This is common in GLP-1 agonists, especially in Semaglutide and Liraglutide.
However, you will usually find that these side effects ease off as your treatment continues and your body gets used to your new medication.
If you experience any side effects while taking this medication, you should speak to a medical professional and ask for their advice.
They will be able to assess how your treatment is going and make sure that Tirzepatide is the right option for you while offering advice to keep your side effects to a minimum.
Mounjaro is made by Eli Lilly, a reputable drug manufacturer that produces a wide range of diabetes medications as well as many other treatments.
Currently, the only GLP-1 receptor agonists licensed for weight loss in the UK (liraglutide and semaglutide) are manufactured by Novo Nordisk.
This creates an interesting outlook for the future of weight loss injections, as it will not only create more choices for patients but could lead to more competitive pricing.
All in all, different manufacturers making the same type of medication will only benefit patients.
Tirzepatide is a prescription-only medication, so you can’t buy it directly.
Instead, you’ll need a prescription from an appropriate medical professional.
Many people find that their GP won’t prescribe weight loss medications, as they have a lot of different boxes they need to check before they can write a prescription for weight loss drugs.
This is where myBMI really shines.
When you come to us, you’ll pay a flat fee* for your consultation with our prescribers.
This fee will also cover the cost of your treatment (which could be one of a range of weight loss medications), delivery from our dispensing pharmacy, and any supporting treatments you may need to help you manage side effects like nausea and headaches.
*If you decide to change to a different treatment after a consultation, the cost of our services may change to reflect the cost of your medication
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