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Can I buy Mounjaro for weight loss in the UK?

Can I buy Mounjaro for weight loss in the UK?

Mounjaro is a once-a-week injection for type-2 diabetes that helps lower your blood sugar. It contains the active ingredient tirzepatide in a pre-filled pen. It can also help you lose weight, but it’s not currently licensed in the UK as a weight-loss treatment. It may be prescribed off-label to help patients lose weight when other treatments and lifestyle changes haven’t worked.

Alexandra Cristina Cowell
Medically reviewed by
Alexandra Cristina Cowell, Writer & Clinical Content Reviewer

Here we’ll tell you more about Mounjaro: how it works, why it helps people lose weight, and if you can buy it without a prescription.

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Medically reviewed by
Dr Alexandra Cristina Cowell
Writer & Clinical Content Reviewer
on August 11, 2023.
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What is Mounjaro?

Mounjaro is a new brand name for a medicine called tirzepatide. It’s used for type-2 diabetes and comes as a pre-filled injection pen that you use once a week. It attaches to two different gut hormone receptors called GIP and GLP-1, which stimulate the release of insulin and help control blood sugar levels, representing a new class of diabetes medication. It also reduces appetite and allows you to feel fuller for longer.

Mounjaro is manufactured by Eli Lilly and is currently the first and only approved once-weekly GIP and GLP-1 receptor agonist, targeting the body’s natural incretin hormones. Just like liraglutide and semaglutide, which are also type-2 diabetes treatments, it could also eventually be licensed as a weight loss treatment (most likely under a different brand name).

How does Mounjaro work?

Mounjaro contains tirzepatide, which works as a dual GIP and GLP-1 receptor agonist. It attaches to receptors for GIP and GLP-1 hormones in your body. When tirzepatide attaches to these receptors, it stimulates the release of insulin from the pancreas, helping to control blood glucose levels.

Tirzepatide also increases the levels of adiponectin, a hormone that plays a role in regulating blood glucose and metabolism. This means it can control your appetite by emptying your stomach more slowly, which helps you eat less frequently because you feel full for longer.

What doses does Mounjaro come in?

Mounjaro comes in various doses to help control your blood glucose levels for type-2 diabetes. It’s available in doses of 2.5mg, 5mg, 7.5mg, 10mg, 12.5mg, and 15mg.
You’ll typically start with the lowest dose, containing 2.5mg of tirzepatide.

After four weeks, this will increase to the 5mg pen. After four weeks on the 5mg dose, your clinician will discuss with you whether the 5mg dose is sufficient for diabetes control or if a higher dose is needed. And again, you’ll stay on the new dose for four weeks before reassessing the dosage.

Are there other medications that use Tirzepatide?

No. Mounjaro is unique because it’s the only diabetic medication that activates both GLP-1 and GIP receptors for better blood sugar control. As it's a relatively new class of diabetic medication, it may eventually be used as a weight loss treatment too.

Who can use Mounjaro?

Mounjaro is specifically for people with type-2 diabetes. It’s typically prescribed when first-line treatments like metformin are not suitable, but it can still be used alongside metformin and other diabetic treatments. It’s not to be used if you have type-1 diabetes.

While Mounjaro has shown it can cause weight loss, it’s not currently prescribed for that purpose. Like some other type-2 diabetes treatments (Ozempic and Rybelsus), Mounjaro can be used off-label for weight loss. This is at the discretion of your clinician, and you’ll have to meet certain criteria as well as have tried other methods to lose weight first.

What side effects will I get with Mounjaro?

An uncommon but potentially very serious side effect of Mounjaro is an inflamed pancreas (acute pancreatitis). If you have severe stomach pain reaching through to your back, nausea, and vomiting, contact your doctor immediately. This is why, if you’ve already had pancreatitis, you should avoid using Mounjaro.

Other common side effects you may experience on Mounjaro are:

  • low blood sugar (hypoglycemia) - especially when used with other diabetic medications, so your dose may need to be lowered
  • nausea,
  • sickness *
  • diarrhoea *
  • constipation
  • headaches
  • allergic reaction
  • indigestion, bloating, gas, burping, heartburn, acid reflux
  • fatigue
  • fast pulse
  • increased levels of pancreatic enzymes in the blood

* These usually happen when you first start using Mounjaro but typically pass after a couple of weeks.

Will Mounjaro help me lose weight?

Tirzepatide binds to GLP-1 and GIP hormone receptors to produce more insulin and also sends signals to your brain to tell it that you’ve eaten and that you’re full by slowing down the production of glucagon. This effect helps you feel fuller for longer, slows down the emptying of your stomach and so reduces your appetite. If you’re on a new low-calorie diet, this biochemical process should help you stick to your new diet.

There have been plenty of studies that have looked at the efficacy of tirzepatide, with some comparing it to other GLP-1 receptor agonists. Up to 90% of people taking Mounjaro reached an A1C (blood sugar test) of under 7%, and there was a weight loss range of 12lb (5mg) to 25lb (15mg).

In a study comparing tirzepatide to semaglutide (Ozempic), tirzepatide was found to be superior to semaglutide at all doses in reducing blood sugar levels and having a greater reduction in body weight too.

Why is Mounjaro now popular for losing weight?

Compared to other weight loss drugs and type-2 diabetic treatments that are used ‘off-label’, Mounjaro is quite innovative in that it uses a double-agonist approach, which appears to result in greater weight loss than single-agonist treatments like Saxenda. It’s possible that it will follow in the footsteps of liraglutide and semaglutide and eventually be licensed as a weight loss treatment (likely under a new name) and become a first-choice due to its efficacy on both blood sugar levels and weight loss.

Comparison studies have shown an average of patients’ A1C being lowered by 2.1% (5 mg, 10 mg, and 15 mg) on Mounjaro compared to 1.9% (1 mg) on Ozempic. Mounjaro also led to a 17–25 pound weight loss, while Ozempic resulted in a 13-pound weight loss.

Where can I buy Mounjaro for weight loss?

Where can I buy Mounjaro for weight loss?

You can’t buy Mounjaro online or straight from pharmacies for weight loss in the UK. You can only get it for type-2 diabetes on a prescription from the NHS. Your private clinician may be able to prescribe it for you ‘off-licence’ or ‘off-label’ if you meet the criteria for obesity (BMI of 30 or greater), or you have a BMI of 27 or above and have a weight-related health condition, and have tried other weight loss management treatments that haven’t worked.

Can I get Mounjaro without a prescription?

No. Mounjaro is only available with a prescription, so you’ll need a doctor to prescribe it for you. This is because it’s only approved for the treatment of type-2 diabetes, so a clinician needs to assess if Mounjaro is suitable and safe for you. They’ll ensure that you’re using the right dose to manage your blood glucose levels effectively.

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