Your guide to GLP-1 medications for weight loss

Undertaking a weight loss journey isn't linear and, it can often feel intimidating — especially if you've tried a number of weight loss methods in the past. But, the use of GLP-1s for those who are overweight or obese is incredibly hopeful thanks to the effectiveness of these medications.

If you're curious about what GLP-1 is and how these medications work for weight loss, we're here to help with this handy guide.

What is GLP-1?

GLP-1, known formally as glucagon-like peptide 1, is produced in the gut and plays a role in insulin secretion after eating [1]. This hormone slows gastric emptying and is involved in satiety [1][2].

The function of the glucagon-like peptide 1 hormone has been replicated in certain medications, which are being used to treat conditions like diabetes and obesity.

But, how do these work, exactly? Let's dive in.

What are GLP-1 medications and how do they work?

GLP-1 receptor agonists represent a class of medications commonly prescribed to treat type 2 diabetes — alongside diet and exercise — without the need for insulin [3]. These medications help to lower blood glucose levels and make it a little easier to manage diabetes.

Alongside the treatment of diabetes, these medications are also incredibly effective for weight loss and they work by mimicking the effects of the naturally occurring hormone GLP-1, which is produced in the body when eating. This hormone stimulates the pancreas and triggers more insulin to be reduced in order to reduce blood sugar levels.

By stimulating the secretion of insulin, and thereby slowing the release of glucagon-like peptides in the body, the control of blood sugar aids weight loss by acting as the body's 'set point'.

The appetite is then reduced, keeping people feeling fuller and satisfied from their meals for longer, without the temptation of overeating.

In order to create long-term health changes, it's recommended that GLP-1 medicines are combined with lifestyle changes and healthy habits like getting quality sleep, moving your body, eating a balanced diet and looking after your emotional health.

GLP-1 medications like Wegovy, Ozempic and Saxenda need to be stored in the fridge.

What medications are GLP-1?

There are a number of GLP-1 medications that you're probably familiar with thanks to their memorable brand names including Ozempic, Wegovy and Saxenda.

Let's take a look at each medication and how it's used.

Ozempic

Ozempic is a simple once-weekly injection containing the active ingredient, semaglutide. It was developed as a treatment to help those with type 2 diabetes control their blood sugar levels and is still used for this treatment in the UK.

Wegovy

Wegovy is a once-weekly injectable medication containing semaglutide, an active ingredient that is commonly used to stabilise blood sugar levels. In the UK, Wegovy is used for weight loss and in the treatment of obesity [4].

It has been studied and trialled as a weight management drug and, when used alongside a calorie deficit and exercise routine, it can be an effective aid to weight loss. And, Wegovy is one of the medications we prescribe as part of the Juniper Programme.

Saxenda

Saxenda is another self-injectable weight loss medication that is steadily becoming a popular weight loss solution. Like Wegovy, it comes as a prefilled pen for injecting. But, while Wegovy only requires a once-weekly injection, Saxenda requires daily injections.

Instead of semaglutide, Saxenda's main active ingredient is liraglutide. This works similarly to emulate the naturally occurring hormone GLP-1 by regulating your appetite and blood sugar levels, which can lead to eating fewer calories and weight loss.

Rybelsus

Rybelsus is a once-daily prescription medication that contains the same active ingredient as Wegovy and Ozempic — semaglutide. Commonly used to treat type 2 diabetes (along with a healthy diet and exercise routine), research has shown that Rybelsus can also help with weight loss.

Unlike the previous 3 medications, which are injections, Rybelsus comes in the form of a tablet, making it easier and more convenient to take each day.

How are GLP-1 medications taken?

As we touched on, GLP-1 drugs are generally administered with an injection and each brand of medication has a different approach. For example, some require daily injections while others are weekly.

It can feel intimidating to self-administer medication via injections but rest assured that your prescribing healthcare professional will direct you on how to approach this.

Your prescribing clinician will also guide you on how often to take the medication and how long you should take it as this will all depend on your personal or family history and any other medications you may be on.

It's important to note that these medications are not designed as a quick fix for weight loss or to control blood sugar levels, but have been designed to work over an extended period of time.

What are the benefits of using GLP-1 medications?

There are a number of benefits of using GLP-1 medications but the major positives lie in the way the drugs can impact the brain and gut. GLP-1 medications can influence the receptors in the gut and brain that are responsible for the effects of the hormone that deals with satiety [5].

While the way it improves blood sugar control and influences weight loss is impressive, these drugs can also play a role in other areas of health.

These include lowering the risk of heart failure, stroke and kidney disease [4], preserving cell-beta function, increasing insulin sensitivity, maintaining cholesterol levels and lowering your chances of thyroid tumours [6][7].

Plus, there are a bunch of other major benefits that aren't directly related to these medications but can occur as a result of losing weight via GLP-1 medications. For example, reducing body weight can positively influence things like your blood pressure and cholesterol levels.

How effective are GLP-1 drugs for weight loss?

Given a myriad of factors, including how your body responds to the medication as well as the different medications available, each person will experience results personal to them on their weight loss journey.

But, to give you an idea of what you can expect, let's look at the clinical study we mentioned above, which analysed the results achieved by nearly 2,000 overweight people across 16 countries, after 68 weeks of taking 2.4mg of semaglutide [8].

By the end of the study, the average weight loss was 14.9%, about half of the participants had lost more than 15% of their body weight and 1 in 3 had lost at least 20%.

However, newer data on Wegovy’s 7.2mg dose show an average weight loss of 20.7% after 72 weeks, putting it nearly on par with GIP/GLP-1 medication Mounjaro in terms of effectiveness [9]. Plus, Wegovy is more affordable than Mounjaro, often making it more faovurable for ongoing weight manafement.

How to know which medication is right for your weight loss journey

For many, weight loss medications are life-changing — especially if you've attempted to lose weight through diet and lifestyle changes, to no avail.

It's also important to note that not all weight loss drugs are created equal. One person may experience zero side effects when starting Mounjaro, while others might be better suited to Wegovy.

Mounjaro vs Wegovy

Both Wegovy and Mounjaro are considered the gold standard when it comes to aiding weight loss efforts. Thus far, the two medications haven't been directly compared to each other in medical trials.

It's long been thought that Mounjaro leads to more significant weight loss outcomes than Wegovy but with recent research, that is changing.

In clinical trials, patients on the highest possible dose of Wegovy lost up to 20.7% of their body weight, compared to 20.9% with Mounjaro at its highest dose — showing that both can be highly effective when used consistently and with the right support [4][5]. With Juniper, Wegovy is delivered as part of a complete programme that includes expert care, coaching, and tracking tools — to help you get the most from your treatment.

This higher dose of Wegovy isn’t available just yet, but it’s expected to launch in the UK soon.

Can you switch from Mounjaro to Wegovy?

From 1 September 2025, Eli Lilly, the manufacturer of Mounjaro (tirzepatide), will increase its UK list price to align with other developed countries. This nationwide change applies to providers including pharmacies, private clinics, and digital platforms.

In response, we’ve lowered the price of our Wegovy programme by 25%, and we’re making it easier for patients to switch without starting over, so that effective treatment remains within reach for as many people as possible.

So, if you've been wondering if you can switch from Mounjaro to Wegovy, the good news is that it's both safe and straightforward.

When making the switch, Juniper patients don’t need to restart at the lowest dose. If clinically appropriate, they can continue at a higher dose aligned with recent treatment history. We also only require a 7-day gap between your last Mounjaro dose and your first Wegovy dose — unlike most providers, who require 28 days.

At Juniper, we make that switch seamless and fully supported — so you can protect your progress without paying more than you need to. Our clinical switching protocol is is simple and safe:

• ‍Review — Your clinician assesses your treatment history and dose tolerance.‍
• Match — If eligible, you start on an equivalent high dose to avoid losing progress.‍
• Transition — Only a 7-day window is required between your last Mounjaro dose and your first Wegovy dose (most providers require 28 days).‍
• Support — Pharmacist check-ins, dose adjustments, and lifestyle guidance keep you on track.

Start your Wegovy switch today →

What are the side effects of GLP-1 medications?

The most common side effects of GLP-1 medications include gastrointestinal symptoms like nausea and vomiting [5]. Other people may find it triggers a reaction at the injection site or causes headaches. Be sure to chat with your doctor if these side effects become too much.

It's also important to note that this medication is safe and effective to take for adults with a BMI of over 30 with a co-morbid condition.

Who shouldn't take GLP-1 medications?

Like all medications, GLP-1 drugs aren't suitable for everyone. People who should steer clear of these medications include those who are pregnant or breastfeeding, as well as those with a personal or family history of medullary thyroid cancer.

Don't use GLP-1 receptor agonists if you, or any of your family, have ever had MTC, or if you have an endocrine system condition called Multiple Endocrine Neoplasia syndrome type 2 (MEN 2).

Those who should use these medications with caution include those with diabetic retinopathy, pancreatitis, gallbladder disease, kidney problems, and stomach/intestinal disorders — such as Gastroparesis and digestion problems.