In recent years, no other medication has created the same media buzz as glucagon-like peptide-1 receptor agonists (GLP-1s). Better known by names like Mounjaro or Ozempic, these treatments are widely recognised for their indirect effects on weight loss. Originally developed for the management of type 2 diabetes,¹ these drugs challenge traditional usage. They raise concerns about the potential health risks from misuse. By providing people with a wider understanding, we aim to empower people to make safe and informed decisions about GLP-1 medications.

Behind GLP-1 success

Prescriptions for these drugs skyrocketed by 300% between 2018-2023,² owing to their unique approach to diabetes management. Unlike traditional medications, GLP-1’s chemically mimic the body’s own GLP-1 hormone, which is released in the intestine after eating.¹ 

Effects Include:

• Releasing insulin from the pancreas: Shifting sugar from the blood into cells³
• Reducing levels of the hormone glucagon: Responsible for raising blood sugar³
• Slowing the rate at which food leaves the stomach: Also known as gastric emptying, this reduces appetite and leaves you feeling full for longer¹ 

Beyond regulating blood sugar, benefits also extend into improved blood pressure and cholesterol levels.⁴ This is important as type 2 diabetes can often lead to heart and circulatory issues, highlighting another mechanism of management. Unlike older diabetic medications, GLP-1s don’t typically cause complications like dangerously low blood sugar levels (hypoglycaemia) or weight gain.⁴ In fact, GLP-1s are actually associated with improved weight loss. 

Their convenience also plays into the success of GLP-1s. With usually once daily or weekly injections and oral formulas, this increases ease and accessibility for a treatment with already established appeal.

History of use

Initially, GLP-1s were first approved for type 2 diabetes, entering the market in the mid 2000s.⁵ However, over time the substantial weight loss seen in clinical trials led to further investigation and recent treatment milestones. Shifting GLP-1 use to include patients whose main issue was obesity.⁴ 

2017

The GLP-1 Liraglutide, sold as Saxenda, was approved by the MHRA for long-term weight management.⁶ The GLP-1 Semaglutide, sold as Wegovy, was approved in the USA for weight loss uses.⁷

2023

NICE recommended Semaglutide, for controlling obesity in UK patients with high BMIs and other weight-related issues.⁸ 

Who can benefit? 

Treatment with GLP-1s are guided by criteria set by NICE. This ensures that it targets those most likely to benefit whilst avoiding risk. 

You may be considered if you are part of any of the following groups:

Highest risk groups

A BMI ≥35 kg/m², or ≥32.5 kg/m² in people of South Asian, Black, or African-Caribbean descent.⁹ In these groups, there is a higher risk of cardiovascular and metabolic disorders. Additionally, you must also present at least one weight-related issue. An example would be if you had either type 2 diabetes, non-alcoholic fatty liver disease, or osteoarthritis.⁹

Other groups

You haven’t achieved adequate blood sugar control using medications like metformin, which improves the way the body handles insulin. GLP-1s are often prescribed when weight loss is a goal. NICE allows for GLP-1s to be taken by those with a BMI under 35 kg/m². However this is only the case if using insulin would affect your job due to the risk of hypoglycaemia, and providing weight loss would lead to improvements in other obesity related health issues.⁹

UK Availability of GLP-1s

It’s important to note that GLP-1s refer to a class of medications, not a single drug. There are different versions within this class, and their clinical relevance depends on the specific needs and circumstances of the patient.

Usage within the UK:

• Exenatide: Now rarely prescribed, this medication was usually taken through either twice daily or once weekly injections to manage type 2 diabetes and help with blood sugar levels⁹
• Liraglutide: Less convenient than other options, this medication is used for both diabetes (sold as Victoza) and for moderate weight loss (sold as Saxenda), requiring doses to be taken daily¹⁰
• Lixisenatide: Now phased out for better alternatives, this daily injection was used for type 2 diabetes management but is no longer available¹¹
• Dulaglutide: With good efficacy and ease of use, this treatment is a good option for patients wanting simple treatment for type 2 diabetes¹²
• Semaglutide: One of the most effective treatments for both blood sugar and weight loss, this is available as a weekly injection (sold as Ozempic or Wegovy) or daily tablet (sold as Rybelsus) and widely used⁸
• Tirzepatide: Identified as one of the strongest options for weight loss, this newer medication is becoming increasingly available on the NHS¹³

Treatment Journey

Like many big changes, starting new medication can often feel overwhelming. Whilst the first month can often be uncharted territory, easing into a new routine and establishing some sense of normal will help you to feel comfortable. 

GLP-1s are usually injected subcutaneously, which means into the fatty layer under your skin. However, if this is a concern, some can be taken orally. Your GP will run through how to safely take these medications.

Common side effects include nausea, vomiting, diarrhoea, and constipation.¹⁴ These are typically most noticeable in the first few weeks as your body adjusts. It’s helpful to keep a symptom and food diary to monitor changes and report back to your healthcare provider. This data helps determine whether the treatment is effective or needs adjusting.⁶

The medications Semaglutide and Liraglutide are usually started at a low dose and increased gradually to reduce side effects.¹⁵ Regular check-ins are essential to assess progress, and ensure you keep safe and well during the course of your treatment.⁶

Are they safe?

Certain patient groups are advised to stop GLP-1 medications, especially if the following occurs: 

• Diabetic ketoacidosis: Build-up of acids, called ketones in the blood due to a lack of insulin⁹
• Digestive issues¹
• Kidney disease⁹
• Severe liver disease⁹
• Pregnant or breastfeeding⁹

Continued Use

GLP-1s work while you take them. If stopped, many people shall regain lost weight unless lifestyle changes are maintained. These medications are most effective when paired with healthy eating, increased activity, and psychological support. NICE currently recommends a maximum treatment period of two years for weight management, specifically with Tirzepatide.¹⁶

Additionally, NICE recommends a "stop rule": patients must show a meaningful response within six months of initiating treatment with Semaglutide, typically defined as a weight loss of at least 3% of baseline body weight and/or a reduction in HbA1c (glycated haemoglobin).⁸ This requirement ensures that ongoing use of these medications is clinically justified and cost-effective.⁸

Future Directions

GLP-1s are being explored for an expanding range of uses:

• Alzheimer's disease: Semaglutide is in phase 3 trials for cognitive decline¹⁵
• Polycystic Ovary Syndrome (PCOS): Studies suggest improved insulin sensitivity and weight outcomes¹⁴
• NAFLD/NASH: Trials show promising liver fat reductions¹⁴
• Addiction: GLP-1s may reduce alcohol and food cravings¹⁷
• Obesity-related cancers: Some evidence points to reduced incidence of certain cancers, such as colorectal and breast cancer¹⁴

These potential indications may redefine the role of GLP-1s in metabolic and neurological care in the next decade.

Summary 

GLP-1 receptor agonists have revolutionized treatment for type 2 diabetes and obesity. Their benefits extend far beyond blood sugar control, offering cardiovascular protection, weight loss, and even potential cognitive health improvements. While not risk-free, these drugs are generally safe when used under medical supervision and targeted to the right patient groups. However, they are not for everyone.

Responsible use includes proper patient selection, ongoing monitoring, and supportive lifestyle changes. Speak to a healthcare provider to assess whether a GLP-1 is the right fit for your personal health goals, and remember that medication is a tool. It is most effective when paired with a long-term commitment to choosing healthy choices and lifestyle adaptations.