Have you been struggling to lose weight through traditional methods like diet and exercise? Weight loss injections might be the solution you’ve been looking for. In recent years, these injections have gained popularity for their ability to help individuals manage their weight by regulating appetite and metabolism.

But how effective are these injections, and what are the potential side effects? In this article, we’ll explore how weight loss injections work, compare the most popular options available in the UK, and help you determine whether these treatments are right for you.

What Are Weight Loss Injections?

Weight loss injections have recently emerged as an effective solution for people struggling to lose weight through traditional methods like diet and exercise. These injections work by regulating the body’s appetite and metabolism, helping patients manage their weight more efficiently.

But what exactly are weight loss injections, and are they suitable for everyone? This article explores the types of weight loss injections available in the UK, their effectiveness, potential side effects, and whether they are the right choice for you.

How Do Weight Loss Injections Work?

Weight loss injections typically work by regulating hormones that control appetite. Most of these treatments contain a type of medication known as GLP-1 receptor agonists. This medication mimics the natural hormone glucagon-like peptide-1 (GLP-1), which is responsible for slowing down digestion, reducing hunger, and regulating blood sugar levels.

As a result, patients feel fuller for longer, leading to reduced calorie intake and, consequently, weight loss. In addition, these injections can also help control blood sugar levels, making them particularly useful for people with conditions like Type 2 diabetes.

Weight Loss Injections

1. Wegovy: A New Type of Weight Loss Medication in the UK

One of the newest additions to the UK weight loss injection market is Wegovy. This injectable medication has shown impressive results, helping patients lose around 15% of their body weight on average. Wegovy contains semaglutide, a GLP-1 receptor agonist that works by suppressing appetite and controlling blood sugar levels.

The injection is administered weekly using a pre-filled pen, similar to how insulin is injected. Clinical trials have demonstrated that Wegovy is highly effective, offering a non-surgical weight loss option for those with a Body Mass Index (BMI) of over 30, or for those with a BMI of over 27.5 if they have other risk factors such as diabetes or high blood pressure.

Side Effects of Wegovy:

While Wegovy is effective, it is important to be aware of its potential side effects, which can include:

• Nausea
• Vomiting
• Diarrhoea
• Constipation

Patients are usually started on a lower dose, which is gradually increased to the maintenance dose to help reduce these side effects.

2. Mounjaro: The Latest and Most Effective Weight Loss Injection

Another recent breakthrough in the world of weight loss injections is Mounjaro. With clinical trials showing an average weight loss of 20%, Mounjaro outperforms most other weight loss treatments, including Wegovy and Saxenda. This injection contains Tirzepatide, a dual GLP-1 and GIP receptor agonist, which not only reduces appetite but also improves how the body processes fat and sugar.

Just like Wegovy, Mounjaro is administered as a once-weekly injection. Patients begin with a 2.5 mg dose, which is increased over time up to a maximum maintenance dose of 15 mg to minimise side effects such as gastrointestinal discomfort.

3. Saxenda: The Original Weight Loss Pen

Saxenda was one of the first GLP-1-based weight loss injections available in the UK, launched in 2020. This treatment uses liraglutide, another GLP-1 receptor agonist, and helps patients achieve around 10% weight loss on average. Unlike Wegovy and Mounjaro, Saxenda is administered daily rather than weekly.

Saxenda works similarly to Wegovy by regulating appetite and food intake. It is prescribed to people with a BMI over 30 or a BMI over 27.5 with additional health risks like hypertension or Type 2 diabetes. Though Saxenda offers slightly less dramatic results compared to newer injections, it remains a reliable option for patients looking to manage their weight effectively​.

4. Ozempic: A Diabetes Drug with Weight Loss Benefits

Although Ozempic is primarily used to treat diabetes, it has gained popularity for its off-label use as a weight loss injection. Ozempic, like Wegovy, contains semaglutide, and many doctors prescribe it to patients who want to lose weight, even though it is not officially licensed for this purpose in the UK.

Doctors prescribing Ozempic for weight loss should do so with caution, particularly as the medication is primarily intended for diabetic patients.

The concern is that overuse for weight loss could affect the supply of this important medication for those who need it for blood sugar regulation. For this reason, many weight loss clinics may choose to prioritise prescribing Wegovy over Ozempic​.

Here’s a detailed table comparing the four weight loss injections: Wegovy, Mounjaro, Saxenda, and Ozempic.

Injection	Active Ingredient	Average Weight Loss	Dosing Schedule	Approved For	Side Effects	BMI Requirement
Wegovy	Semaglutide	~15%	Once weekly	Chronic weight management, heart health benefits in certain patients​	Nausea, vomiting, diarrhoea, constipation	BMI > 30, or > 27.5 with risk factors
Mounjaro	Tirzepatide	~20%	Once weekly	Primarily for Type 2 diabetes, but also effective for weight loss	Nausea, vomiting, diarrhoea, indigestion	BMI > 30, or > 27.5 with risk factors
Saxenda	Liraglutide	~10%	Once daily	Weight management for obesity​	Nausea, vomiting, diarrhoea, increased heart rate	BMI > 30, or > 27.5 with risk factors
Ozempic	Semaglutide	~10% (off-label for weight loss)	Once weekly	Type 2 diabetes (off-label for weight loss)	Nausea, vomiting, diarrhoea, possible thyroid issues	Typically for diabetes, but off-label use for weight loss

Benefits and Risks of Weight Loss Injections

Benefits:

• Effective weight loss: Wegovy, Saxenda, Mounjaro, and Ozempic have all demonstrated significant weight loss results in clinical trials.
• Non-surgical solution: Weight loss injections offer an alternative to invasive surgical procedures like gastric bypass.
• Health improvements: Weight loss injections can help reduce the risk of developing obesity-related conditions such as heart disease, stroke, and diabetes.

Risks:

• Gastrointestinal issues: Common side effects include nausea, vomiting, and diarrhoea, especially in the early stages of treatment.
• Long-term side effects: Some concerns have been raised about the long-term safety of GLP-1 receptor agonists, although research continues to show they are generally safe for use​.

Are Weight Loss Injections Right for You?

Weight loss injections are not for everyone. They are typically prescribed for patients with a BMI over 30, or over 27.5 with additional health risks such as high blood pressure or Type 2 diabetes.

Before starting any weight loss injection, it is important to consult with a healthcare professional to ensure it is the right treatment for your specific situation. Weight loss injections should always be used in combination with a healthy diet and regular physical activity for the best results.

Conclusion

Weight loss injections, such as Wegovy, Mounjaro, Saxenda, and Ozempic, are effective treatments for managing weight in people who meet specific criteria. While each offers varying levels of weight loss, they all work by suppressing appetite and regulating blood sugar, helping individuals achieve significant weight loss without surgery.

However, potential side effects and long-term health impacts must be considered before starting these treatments. Consulting with a medical professional will ensure you receive the best guidance on whether weight loss injections are a suitable option for you.

FAQs

What is the average weight loss with Wegovy?

Wegovy helps patients lose around 15% of their body weight on average.

How does Mounjaro compare to other weight loss injections?

Mounjaro is the most effective weight loss injection, with an average weight loss of 20%, compared to 10% for Saxenda and 15% for Wegovy.

Can I use Ozempic for weight loss if I don’t have diabetes?

Yes, but Ozempic is primarily licensed for diabetes treatment, and its off-label use for weight loss should be done under medical supervision.

Are there long-term risks of weight loss injections?

Common risks include gastrointestinal issues like nausea and vomiting, but long-term safety is still being studied.

How long should I stay on a weight loss injection like Saxenda?

This varies by individual and should be discussed with a healthcare provider. Most treatments are continued for several months to a year.

What are the common side effects of semaglutide-based injections?

Nausea, vomiting, diarrhoea, and constipation are the most common side effects.

Who qualifies for weight loss injections in the UK?

Patients with a BMI over 30 or over 27.5 with additional risk factors may qualify.