GLP-1 Medications for Weight Loss

Glucagon-like peptide-1 (GLP-1) receptor agonists are popular weight loss treatments in the UK, with an estimated 1.5 million people accessing them. Their ability to manage blood sugar levels, reduce hunger, and help people eat less to support weight loss is contributing to their popularity.

Additionally, clinical trials data demonstrates that GLP-1 medications like Mounjaro can help you lose an average 22.5% of your initial body weight in just 72 weeks – making them an effective solution, especially for people who may have previously struggled to lose weight.

However, despite their popularity, GLP-1 agonists may not be suitable for everyone. In this guide, we discuss who GLP-1 medications are for, how they work, their effectiveness, and potential side effects you should be aware of before starting treatment.

GLP-1 receptor agonists are a type of medication that mimic the effects of a naturally occurring hormone called glucagon-like peptide 1, which is released after eating.

They work by attaching to GLP-1 receptors in the body to:

These actions help treat obesity and type 2 diabetes.

Currently, GLP-1 medications are delivered by self-injectable pens. Your doctor or nurse can explain how to use them, and information on injecting them will be included with your medication.

➤ We also have an in-depth guide and information on how to inject Mounjaro safely.

GLP-1 medications are injected into specific areas of the body, such as the abdomen, thighs, or upper arms, either weekly or daily, depending on which type of injection you are prescribed. However, a new GLP-1 medication in the form of a pill is currently in development, which contains the active ingredient orforglipron.

Several GLP-1 medications are available in the UK, including the weight loss injections Mounjaro, Wegovy, and Nevolat. They all work in similar ways, but may contain different active ingredients, dosages, and schedules. All GLP-1 medications require a prescription, and a doctor must check they’re suitable for you before you can obtain them.

Wegovy

Wegovy contains the active ingredient semaglutide and is licensed for weight loss in the UK. It is a once-weekly injection that helps to reduce appetite, slow digestion, and keep you feeling fuller for longer. Wegovy has been shown to support people in losing an average 21% of their starting body weight.

Mounjaro

Mounjaro is a once-weekly injection approved for weight loss and type 2 diabetes in the UK. It contains the active ingredient tirzepatide, which activates both GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) receptors to regulate your appetite, slow digestion, increase the feeling of fullness, and manage blood sugar levels, contributing to weight loss.

At the maximum dose of 15mg per week, Mounjaro can help you lose an average 22.5% of your starting body weight after 72 weeks.

Nevolat

Nevolat contains the active ingredient liraglutide, which was formerly available under the brand name Saxenda. Unlike the other GLP-1 injections, Nevolat is a daily medication that can support an average weight loss of 8% over 56 weeks at the highest dose.

Ozempic

Ozempic contains the same active ingredient as Wegovy (semaglutide), but is only available for the treatment of type 2 diabetes in the UK. Wegovy is a licensed treatment approved and recommended specifically for weight loss that contains the same active ingredient.

Ozempic works in the same way as Wegovy, and it is available in a lower dose. Research indicates that 52 to 62% of individuals lose at least 5% of their initial body weight within 1 year.

Orforglipron

Orforglipron is a new GLP-1 medication which is currently being developed by Eli Lilly to manage weight and type 2 diabetes. The main difference between orforglipron and other GLP-1 treatments, like Wegovy, Mounjaro, and Nevolat, is that it will be available in oral tablet form.

The effectiveness of GLP-1 medications will depend on the active ingredient or brand. Clinical research continues to show that they are highly effective for weight management, with significant losses being consistently reported. However, GLP-1 medications will not work on their own, and the best results occur when they are taken along with positive, healthy diet and exercise changes.

Despite their effectiveness for weight loss, GLP-1 medications can cause side effects in some people, although not everyone will get them. Some of the most common side effects of GLP-1 medications are:

• feeling sick (nausea)
• being sick (vomiting)
• diarrhoea
• constipation
• gas
• bloating
• abdominal pain
• headaches
• dizziness
• weakness or tiredness
• mood changes
• injection site reactions

Rarely, GLP-1 agonists can cause serious side effects, such as:

• allergic reactions
• an inflamed pancreas (pancreatitis)
• kidney or bladder stones
• hip fractures

If you get any of these, you should speak to a doctor straight away or go to A&E in an emergency.

Please note that this list is not exhaustive, you can read more about the side effects of Mounjaro, Wegovy, Nevolat, Ozempic and Orforglipron in the patient information leaflets included with them.

GLP-1 receptor agonists are potent medications and are not suitable for everyone. That’s why you will need a consultation with a doctor before you can get them, so that they can ensure they are safe and suitable for you to take. In most cases, GLP-1 medications can be prescribed to you if you have a body mass index (BMI) of:

• 30 or more
• 27 to 29.9 and you have a weight-related medical condition, such as high blood pressure, obstructive sleep apnoea, or high blood fat levels

GLP-1 medications can only be used by overweight or obese individuals. They are not suitable if you are pregnant or trying to get pregnant or if you have certain medical conditions, like kidney failure, liver disease, or pancreatitis.

GLP-1 receptor agonists are only available with a prescription in the UK, either privately or on the NHS. Some types, like Mounjaro, can be prescribed via your GP, while for Wegovy, you will need to be referred to a specialist weight management clinic for a prescription.

Weight loss injections are not available over the counter.

You can request Wegovy, Mounjaro, and Nevolat from Superdrug Online Doctor after completing a short online health questionnaire, which allows one of our doctors to review and ensure the medication is safe for you. You will need to provide some photos and answer the questions honestly, and have a BMI of at least 30 or 27 or more and weight-related health conditions.

If you choose to access weight loss injections via the NHS, you will need to meet the following:

Wegovy (semaglutide)

After being successfully referred to a tier 3 weight management specialist, you’ll need a BMI of:

• 35 or more, or 32.5 if you are Asian, Chinese, Middle Eastern, Black African, or African-Caribbean
• 30 to 34.9, or 27.5 to 32.4 if you are Asian, Chinese, Middle Eastern, Black African, or African-Caribbean, and meet any other criteria set out by a specialist weight management service

Nevolat (liraglutide)

You will only be prescribed Nevolat on the NHS if you have:

• a BMI of 35 or more, or at least 32.5 if you are Asian, Chinese, Middle Eastern, Black African, or African-Caribbean
• non-diabetic high blood sugar
• a high chance of heart problems

Mounjaro (tirzepatide)

You may be able to get Mounjaro on the NHS from your GP if you have a BMI of at least 40 and 4 or more of the following conditions:

• type 2 diabetes
• high blood pressure
• heart disease
• high blood fats
• obstructive sleep apnoea

According to NHS guidelines, only people with these 5 conditions are considered for Mounjaro prescriptions.

It is possible to switch between GLP-1 medications if you think that your current injection is not working for you or if you are getting side effects that you find difficult to manage. Safe switching involves stopping your current treatment, waiting the usual 7 days between injections, and starting your new treatment on the same day your next dose was due.

So, if you are switching from Mounjaro to Wegovy, you will need to start your first Wegovy injection 1 week after your last Mounjaro dose, which is the same break you have between doses of Wegovy. The maximum dose of Wegovy you can switch to is based on your current Mounjaro dose:

Equally, if you decide to switch from Wegovy to Mounjaro, you’ll wait your usual 1 week between your last Wegovy injection and your first Mounjaro one. This means you can continue treatment without having to take a break from weight loss medication.

If you were on a dose of up to 1mg a week on Wegovy, you’ll start on the lowest dose of Mounjaro, which is 2.5mg. If you’re on a higher dose, you’ll start on 5mg of Mounjaro, the second dose.

Switching is easy and safe under the guidance of a doctor. If you are new to Superdrug Online Doctor, you will need to request the weight loss injection you would like to switch to, and one of our doctors will check if it is safe and suitable for you to do so.

If you already have a Superdrug Online Doctor patient account, simply submit a health questionnaire to inform us of the GLP-1 medication you would like to switch to. One of our doctors will verify that the medication you have chosen is suitable for you.

If weight loss injections are not for you, alternatives are available. Some people find that the side effects of GLP-1 medications are difficult to manage, or have a fear of needles, or do not like the idea of having to inject themselves with medication. If this sounds like you, prescription weight loss pills may be a better option.

Orlistat

Orlistat is a prescription-only weight loss medication that works by blocking the absorption of fat from your diet, supporting weight loss. Orlistat is also available under the brand name Xenical. Each pill contains 120mg of orlistat and can be taken up to 3 times a day.

Research indicates that 37% of individuals who take orlistat lose at least 5% of their body weight within 12 weeks.

Orlistat is also available as an over-the-counter version called alli, which contains 60mg of the active ingredient. It is taken in exactly the same way and works by blocking the absorption of dietary fat. However, rather than requiring a prescription from a doctor, you will need to answer a few questions with a pharmacist before you can purchase it.

MySimba

MySimba contains 2 active ingredients, naltrexone hydrochloride and bupropion hydrochloride. Together, they work to support weight loss by suppressing your appetite and helping you stay fuller for longer. MySimba is taken daily, with the dose increasing over 4 weeks until you are taking 4 tablets per day (2 in the morning and 2 in the evening). MySimba can help you lose an average of 8.1% of your starting body weight over 56 weeks.

GLP-1 medications are gaining popularity due to their effectiveness in increasing weight loss results. However, they do not work on their own and require additional lifestyle changes, including following a balanced, calorie-controlled diet and increasing your exercise.

They are also not suitable for everyone. For example, they can cause side effects, which may be difficult for some people to manage, and require you to administer the medication yourself via an injection, which can put some people off. Several alternative weight loss treatments are available if GLP-1 medications are not the right option for you.

What’s the difference between Wegovy, Mounjaro, and Ozempic?

Wegovy, Mounjaro, and Ozempic are all GLP-1 receptor agonists that come as once-weekly, injectable pens, but they contain different active ingredients and have been approved for different purposes. Wegovy and Ozempic contain the active ingredient semaglutide, but only Wegovy is approved for weight loss, while Ozempic is used to treat type 2 diabetes. They also contain different strengths of the active ingredient.

Mounjaro, on the other hand, can be prescribed for weight loss or type 2 diabetes and contains the active ingredient tirzepatide. It also has a dual action because it mimics the effects of 2 digestive hormones, GLP-1 and GIP.

How much weight can you lose with GLP-1 injections?

The weight loss potential of GLP-1 injections depends on the medication that’s prescribed. Mounjaro can help you lose an average of 22.5% of your starting body weight over 72 weeks at the highest dose, while Wegovy has been shown to promote up to a 21% average weight loss over 72 weeks. Nevolat can cause an average weight loss of 8% over 56 weeks. However, these are just averages, and your body may respond differently to the medication. You will also need to make healthy lifestyle changes to fully benefit from weight loss injections.

Can you stop taking GLP-1 once you reach your goal weight?

Yes, although your doctor may recommend switching to a maintenance dose to help you maintain your weight loss. The dose will be decided by your doctor, and can either be your current dose or a lower dose. You will also receive ongoing support to help you stick to your healthy lifestyle choices.

Are GLP-1 injections safe for long-term use?

Yes, weight loss injections are a safe treatment, and your doctor will monitor your response regularly. Some studies have researched GLP-1 medications for 2 years and reported mostly mild to moderate gastrointestinal side effects.