Key Takeaways

• Powerful Tools for Health: GLP-1 receptor agonists (like semaglutide, liraglutide, dulaglutide) and the newer dual-action agonist Tirzepatide are highly effective injectable medications for significantly improving blood sugar control in type 2 diabetes and promoting substantial weight loss in individuals with obesity or excess weight.

• Tirzepatide's Enhanced Impact: Tirzepatide, which acts on two hormone receptors (GLP-1 and GIP), has demonstrated superior results in clinical trials for both weight loss and blood sugar management when compared to some GLP-1 RAs that target only one receptor.

• Beyond Core Benefits: Beyond diabetes and weight management, this class of medications offers proven benefits for heart and kidney health, with emerging research highlighting potential advantages for liver health and reducing certain cravings.

• Holistic Approach is Crucial: These are prescription medications that work best as part of a comprehensive plan that includesa healthy diet, regular physical activity, and ongoing medical guidance to manage potential side effects and sustain long-term benefits.

Although healthy lifestyle changes are a cornerstone of the treatment plan for people with diabetes and for weight management, medications can also be a vital tool for many. Several different medication options are available that can be helpful in gaining better control of blood sugar and supporting weight loss. Among these is a class of medications known as GLP-1 receptor agonists (GLP-1 RAs). A newer medication, tirzepatide, which targets two hormone receptors (GLP-1 and GIP), is also an important option offering significant benefits.

GLP-1 RAs include established medications like semaglutide, liraglutide, and dulaglutide. These medications, alongside tirzepatide, not only help control blood sugar but can also lead to significant weight loss, with some specifically approved for this purpose.

Which GLP-1 RAs and Dual-Action Agonists are Available in Singapore?

Certain GLP-1 RAs are approved specifically to promote weight loss, while others are primarily approved for treating diabetes, though they may also assist with weight. In Singapore, liraglutide and a form of semaglutide are approved for weight loss. 

For treating diabetes, options include different forms of semaglutide, dulaglutide, and tirzepatide. While many of these medications can lead to weight loss, their primary approval and prescription purpose should always be discussed with your doctor.

Key Benefits of GLP-1 Receptor Agonists and Dual-Action Agonists

These medications offer a range of benefits, particularly for individuals managing type 2 diabetes and those seeking support for weight loss.

Blood sugar control

Diabetes is a condition in which a person's blood sugar levels are consistently higher than usual. Keeping blood sugar under control is crucial for reducing the risk of long-term complications such as vision loss, kidney disease, and nerve damage. Diabetes is usually diagnosed when a person has a fasting blood sugar level of 7.0 mmol/L (126 mg/dL) or higher, or a haemoglobin A1c (HbA1c) level of 6.5% or higher.

GLP-1 RAs and dual-action agonists like tirzepatide have been shown to control blood sugar effectively, making them a viable option for many diabetes patients. They can be used on their own, in conjunction with lifestyle changes like exercise and a healthy diet. If needed, they can also be combined with other diabetes medications.

Weight Management

These medications have also been shown to result in significant weight loss, which may in turn help to reduce the risk of diabetes complications and other obesity-related conditions. 

Enhanced Efficacy with Dual-Action Medications: Newer agents like tirzepatide, which target both GLP-1 and GIP receptors, have often demonstrated superior blood sugar lowering and more significant weight loss in clinical trials compared to GLP-1 RAs that only target one receptor. Clinical studies have shown that dual-action agonists like tirzepatide can lead to more significant reductions in blood sugar and body weight for many patients compared to some other GLP-1 RAs. This can be a crucial factor for individuals needing more intensive management.

Further highlighting its strong performance in weight management, a significant 72-week phase 3b clinical trial (known as SURMOUNT-5) directly compared tirzepatide with semaglutide in adults with obesity who did not have type 2 diabetes. The results were compelling: participants receiving tirzepatide achieved an average weight loss of -20.2% from their baseline weight, compared to -13.7% for those treated with semaglutide. Additionally, those on tirzepatide experienced a greater reduction in waist circumference (average of -18.4 cm vs. -13.0 cm) and were more likely to achieve higher thresholds of weight loss, including 20% and 25% or more. These findings underscore the significant efficacy tirzepatide can offer for individuals focused specifically on obesity management. As with all GLP-1 RAs, the most common side effects noted were gastrointestinal and generally mild to moderate.

To be considered a candidate for receiving one of these medications for weight loss, a person typically must have a body mass index (BMI) indicating obesity, or a lower BMI if they are already experiencing complications due to their body weight (such as type 2 diabetes, high blood pressure, or high cholesterol).

Based on available scientific research, the World Health Organization recommends slightly different cutoffs in body weight targets for Asian and non-Asian populations. To be a candidate for receiving such a medication for weight loss, a person generally needs to meet one of the following criteria:

• For non-Asians, a BMI of 30 or greater (indicating obesity), or a BMI of 27 or greater along with health complications of being overweight.

• For Asians, a BMI of 27.5 or greater (indicating obesity), or a BMI of 23 or greater along with health complications of being overweight.

Heart and Kidney Protection

GLP-1 RAs have been shown to have significant benefits for both the heart and kidneys. Semaglutide, for example, has been shown to reduce the risk of major adverse cardiovascular events such as heart attack and stroke.

In addition, these medications can reduce the risk of kidney disease progression. For instance, studies have shown that some GLP-1 RAs can lead to improvements in kidney function markers for people with diabetes.

Emerging and Broader Health Benefits

Beyond the well-established benefits, research is revealing even more ways these medications can support overall health:

• Potential Liver Health Benefits: Emerging research suggests that GLP-1 RAs and tirzepatide may improve liver health, particularly in individuals with conditions like non-alcoholic fatty liver disease (NAFLD) or its more severe form, non-alcoholic steatohepatitis (MASH). They can help reduce liver fat and inflammation.

• Neuroprotective Possibilities: There is growing interest and early research into the potential neuroprotective effects of GLP-1 RAs. Studies are exploring their role in potentially reducing the risk or slowing the progression of neurodegenerative diseases like Alzheimer's and Parkinson's disease, though more research is needed to confirm these effects.

• Support in Reducing Certain Cravings: Some evidence indicates that these medications might play a role in modulating the brain's reward pathways, potentially helping to reduce cravings for certain foods and possibly even impacting addictive behaviours, such as those related to alcohol consumption. This area is still under active investigation.

• Improvements in Sleep Apnoea: For individuals with obesity-related obstructive sleep apnoea (OSA), the significant weight loss often achieved with these medications can lead to notable improvements in OSA symptoms and severity.

Further Cardiovascular Protection: Beyond reducing risks of heart attack and stroke, some GLP-1 RAs have shown benefits in specific types of heart failure, such as heart failure with preserved ejection fraction (HFpEF), and may also help by reducing overall inflammation, a key factor in cardiovascular disease.

How to Get the Most Benefit from GLP-1 RAs (including Semaglutide, Liraglutide, Dulaglutide, and Tirzepatide)

To maximize the effectiveness of these medications, it is highly recommended to work on optimizing your diet and physical activity levels concurrently.

Improving your nutrition and physical fitness will aid glucose control, boost your energy levels, and help you get the most out of your day. It will also be crucial for sustaining any weight loss achieved and for long-term health.

Potential Side Effects of GLP-1 RAs (including Semaglutide, Liraglutide, Dulaglutide, and Tirzepatide)

Like all medications, GLP-1 RAs and dual-action agonists can have side effects. Some of the most common side effects include:

• Nausea and Vomiting

• Diarrhoea or Constipation

• Bloating

• Headache

• Heartburn

• Abdominal Pain

• Burping or Indigestion

• Allergic Reaction (such as hives, swelling, or rash) – this is rare but can be serious

These side effects are often mild to moderate, may be uncomfortable, but are usually not dangerous and tend to decrease over time as your body adjusts. However, an allergic reaction can be serious and should be reported to your doctor immediately.

If you experience any persistent or bothersome side effects, you should consult your doctor to review your treatment plan. In many cases, lifestyle adjustments or changes to how the medication is taken can help manage them. It’s also common for doctors to start with a lower dose and gradually increase it; this helps give the body time to get used to the medication, which tends to reduce side effects.

Where can I buy Semaglutide, Liraglutide, Tirzepatide, and other GLP-1 RAs in Singapore?

These medications are not available over the counter. They can only be obtained by prescription, so you will need to consult a doctor to discuss whether they are appropriate for you and to get them. Not all clinics in Singapore may carry all types of GLP-1 RAs or dual-action agonists, so if this is an option you’d like to explore, it's a good idea to call the clinic to check before making an appointment.

Medication alone isn’t a complete solution. GLP-1 RAs and similar medications, whether for weight loss or diabetes management, are most effective when paired with sustainable, healthy lifestyle habits that support long-term well-being.