Mounjaro
- Genuine UK medicine
- Click and collect in as little as 24 hours
- From a high street name you can trust
Mounjaro (tirzepatide) is a weight loss treatment that comes in the form of
a weekly self-injectable pen.
We can prescribe Mounjaro if it’s suitable for you. Find out more about our
weight loss treatment service.
Find out more about our weight loss treatment service.
Mounjaro is an injection pen used for weight loss and to treat type 2
diabetes.
They are exactly the same medicine containing the same active ingredient
(tirzepatide) and work in exactly the same way. The difference is the name:
Zepbound is the US name for the weight loss management medicine, whereas in
the UK it’s licensed under the name Mounjaro. Zepbound is not licensed in
the UK.
The active ingredient in Mounjaro is called tirzepatide.
Tirzepatide works on two different hormonal receptors: glucagon-like
peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP).
You may have heard of GLP-1 from other weight loss injections.
GLP-1 helps to regulate blood sugar levels, which in turn talks to the brain
to make you feel less hungry and prevent cravings. It also slows down the
emptying of the stomach to keep you feeling fuller for longer.
GIP regulates energy balance in brain and fat cells, enhancing the GLP-1
effect of suppressing your appetite and improving sugar control.
By mimicking the effects of both these naturally occurring hormones,
Mounjaro has been shown to have greater weight loss potential than medicines
that work on GLP-1 alone.
You inject Mounjaro under the skin (subcutaneously) in your stomach area,
thigh or upper arm once a week using an injection pen. Don’t worry, it’s
actually much easier than it sounds and if we prescribe Mounjaro for you,
we’ll provide you with full instructions on how to use it.
You must follow a strict dosage increase schedule as advised by your
healthcare provider.
To allow your body to get used to the medicine and have the best chance for
long-term success, you should follow the gently increasing dosage schedule
as instructed.
Usually, you’ll start with a dose of 2.5 mg of Mounjaro, which will increase
every four weeks (or as advised and if suitable for you) until you reach
your maximum maintenance dose of 5mg, 10mg or 15mg.
If you’re wondering how much weight you can lose on Mounjaro, clinical
trials have shown that patients could achieve at least 20% weight loss after
using tirzepatide for 72 weeks (18 months) when combined with healthy
lifestyle changes.
Mounjaro can cause some side effects to occur. Very common ones are
gastrointestinal in nature: nausea, vomiting, diarrhoea and constipation.
These are mainly seen with dose increases, and tend to settle with time.
Other common side effects could include: fatigue, feeling lightheaded,
excess wind (flatulence), gallstones, gastroesophageal reflux, injection
site reactions, hair loss and hypoglycemia in patients with type 2 diabetes.
In rare cases, there can be serious side effects, such as:
Pancreatitis – if you develop severe abdominal pain, with or without
persistent vomiting, this may be a sign of pancreatitis and you need to get
medical help immediately.
Anaphylaxis – if you experience difficulty breathing, swelling of the face,
lips or tongue and difficulty swallowing, you may be having a severe
allergic reaction (anaphylaxis) and you must seek immediate medical help.
Please read the
Patient Information Leaflet
that comes with your medicine for full details of side effects and how to
use Mounjaro.
Mounjaro is approved for people with a BMI over 30 (obesity), as well as
those with a BMI over 27 (overweight) who also have weight-related health
problems such as prediabetes, high blood pressure, high cholesterol, or
heart problems.
You shouldn’t use tirzepatide if you’re pregnant, and you should stop taking
Mounjaro at least one month before trying to get pregnant.
Mounjaro is not suitable in some medical circumstances, for example if you
use some other diabetes medicines, have severe problems with digesting food,
or have a history of pancreatitis or thyroid cancer. If you’re allergic to
tirzepatide or any of the other ingredients in this weight loss injection
treatment, you must not use Mounjaro.
It’s essential that you give us a full medical history and details of any
conditions or other medicines you’re taking when you fill out our online
questionnaire. This ensures we’re able to prescribe weight loss treatment
that’s suitable and safe for you.
As Mounjaro is a new weight loss medicine available in the UK, it has been
assigned a black triangle, which means it will be closely monitored for any
adverse effects.
We can also prescribe other medicines to help support your weight loss and
weight management journey. Wegovy and Saxenda are weight loss injection
treatments that work similarly to Mounjaro. Orlistat and Xenical are capsule
medicines that work by helping your body get rid of the extra fat in your
diet.
Making healthy lifestyle changes, such as improving your diet and increasing
activity, can help with weight loss and also help you to live a healthier,
happier life.
At Boots Online Doctor, we offer more than medicine. Check out our
free online webinars where
our expert Lifestyle Medicine team offers advice and guidance on weight
loss. We also have a
free 10-week weight loss programme
filled with helpful videos and articles. You may also want to read about
how diet affects your mood and our
recommended eating guides.
Common Mounjaro side effects should be mild and are likely to lessen or even
disappear after your body gets used to the treatment. We understand that
it’s still tough to live with these discomforts though and so we’ve put
together some tips for managing these where possible:
For more information on managing side effects and what to do if you
experience more severe side effects, see our
dedicated weight loss medicine side effects page.
The best places to inject Mounjaro are ones with the most fat. These are:
your tummy (although make sure to inject more than 5cm away from your belly
button); the front of your thighs; or your upper arms. It’s important that
you change injection sites regularly. You can inject in the same area (e.g.
tummy) but choose a different spot in that area each time.
Mounjaro should start working straight away, but it could take several weeks
until it has a noticeable effect on regulating your blood sugar level and
impacting your appetite and eating habits.
If you’re using Saxenda or Wegovy and don’t have any significant side
effects, you can switch to Mounjaro on your next weekly scheduled injection
day. If you have side effects you should wait for these to pass before
switching to Mounjaro.
All patients using Mounjaro for the first time will start with 2.5mg. Keep
in mind, Mounjaro may not be suitable for you (even if you're using another
weight loss medicine). We’ll assess if it’s right for you during your
consultation.
Wegovy and Mounjaro are both weekly injection pens and work in similar ways
to aid weight loss. Mounjaro has proven more effective in clinical trials,
as it works on GLP-1 and GIP hormones, whereas Wegovy only works on GLP-1.
However, Mounjaro is a new medicine in the UK so we don’t have as much
safety data on it compared to other medicines in the long term. Deciding if
or which medicine is right for you will depend on different factors, which
we’ll assess during your consultation. If you’re already on Wegovy (or
Saxenda) and losing weight, we recommend you keep using it. Keep in mind,
weight plateaus are normal on your weight loss journey.
The ‘instructions for use’ that come with the pen advise that you use swabs
- you can purchase these in your Boots store when you collect your pen, or
online.
Yes. If you’re using weight loss treatment and are struggling with your
mental health or need some extra help, we’re here. Visit our
mental health support hub
to find out how we can support you.You can also reach out through your
patient record, or book a consultation with one of our clinical team through
our
Depression and Anxiety Treatment service, where we’ll find the right
support and treatment for you.
You can also check out our free Boots Online Doctor podcast dedicated to
managing stress:
Your Better Mental Wellbeing, available to all.
For more information on the help available, visit our dedicated mental
health support page.
What is Mounjaro?
What is Mounjaro used for?
What’s the difference between Mounjaro and Zepbound?
How does Mounjaro work?
How to use Mounjaro
Mounjaro dosage
Is Mounjaro effective?
What are the main side effects of Mounjaro?
What else should I know about Mounjaro?
What are alternative weight loss treatments?
What are the non-drug alternatives to Mounjaro?
How to manage the side effects of Mounjaro
Where should I inject Mounjaro?
How long does it take for Mounjaro to work?
Can I switch from Wegovy to Mounjaro?
Which treatment should I choose, Wegovy or Mounjaro?
Does Mounjaro come with swabs?
Is mental health support available for weight loss patients?
Dr Anju is Clinical Lead for the Weight Loss service and Menopause Advisor. She is SCOPE certified (international gold standard for obesity management) and has a wealth of expertise across clinical medicine, general practice and digital healthcare.