GLP-1/ Weight Loss Injections

For many individuals, weight loss has been a life-long battle often characterised by ‘yo-yo’ weight gain. Weight loss is never sustained and weight gain after weight loss keeps happening such that the individual’s weight moves up and down like a yo-yo. Diet and exercise works but only temporarily for these individuals. The issue is these individuals have a set-point weight that the body is trying to get back to every time weight loss occurs. Hormones such as ghrelin which is responsible for hunger go through the roof with weight loss below this set-point. It isn’t just a matter of willpower that results in weight loss failure. These biological barriers can make it difficult to achieve meaningful results through diet and exercise alone.

Obesity is now considered a chronic disease that in some individuals requires treatment. Diet and exercise is still first line but when it fails, GLP-1 receptor agonists offer a medically supported solution. Originally developed to treat type 2 diabetes, these injectable medications have been found to support substantial weight loss by influencing the body’s natural signals for hunger and satiety. By helping you feel full sooner, reducing cravings, and lowering the aforementioned weight set-point, they address the root causes that often stand in the way of sustainable weight loss.

When prescribed and monitored by a healthcare professional, GLP-1 therapy can be a powerful tool for improving metabolic health and lowering the risks associated with obesity — including cardiovascular disease and type 2 diabetes.

What are GLP-1/ weight loss injections? 

GLP-1 receptor agonists are a class of injectable medications that mimic the action of a naturally occurring hormone secreted by the small intestine in response to food entering the small intestine. The hormone is called glucagon-like peptide 1(GLP-1) and is one of many gastrointestinal peptides that are released by the small intestine. It plays a crucial role in regulating appetite, insulin secretion, and blood sugar levels after meals. GLP-1 travels to the brain and influences the appetite centres, promoting satiety and reducing hunger. Mechanically, it slows down stomach emptying which also makes you feel more full after a meal. This helps manage food intake and gets the individual into a negative calorie balance which will then result in weight loss. 

In individuals struggling with excess weight or obesity, these hormonal responses are thought to be impaired. GLP-1 receptor agonists work by replicating the function of natural GLP-1, helping to restore these deficiencies. By reducing hunger (and ameliorating the constant sense of deprivation often experienced with decreased portion sizes), prolonging the feeling of fullness after eating and, preventing over-eating, and reducing high-fat/ sugar cravings due to their natural effect on the brain’s reward system, they support gradual and sustainable weight loss when combined with dietary and lifestyle changes.

Several GLP-1 medications have been approved for weight management and type 2 diabetes. While brand names vary, the active ingredients are typically part of the GLP-1 analogue family, each with slightly different potency, dosing and duration of action.

How do GLP-1/ weight loss injections work? 

Together, these actions create a metabolic environment that supports steady, clinically meaningful weight loss. Studies have shown that patients using GLP-1 receptor agonists, alongside lifestyle modifications, can achieve an average weight reduction of 10–15% of their body weight over time — with improvements in blood sugar control, blood pressure, and cholesterol levels. 

GLP-1 injections are typically administered once weekly, depending on the specific formulation, and are most effective when combined with a structured care plan that includes nutritional support, physical activity, and regular medical follow-up. Their dosage and dosage uptitration need to be supervised by an experienced physician, ideally an endocrinologist experienced with GLP-1 agonists.

Apart from weight loss, what are the potential benefits of GLP-1 injections? 

GLP-1 receptor agonists offer a wide range of clinically supported benefits for individuals aiming to lose weight and improve their metabolic health. While their primary role is to assist with weight reduction, the advantages of GLP-1 therapy extend well beyond the number on the scale.

Here are some other key benefits:

• Improved blood sugar regulation — GLP-1 receptor agonists enhance insulin secretion in response to meals and reduce glucagon release (a hormone that increases blood sugar), which helps in maintaining stable blood glucose levels. This works in a glucose-dependant fashion with it only working if blood sugar is elevated. Thus it does not cause low blood sugar. This is particularly helpful for individuals with insulin resistance or type 2 diabetes (link to service page).

• Reduced risk of cardiovascular disease — several large-scale studies have found that GLP-1 therapy can lower the risk of major cardiovascular events, including heart attack and stroke, in people with type 2 diabetes with or without previous heart disease.

• Lower blood pressure and improved cholesterol levels — weight loss induced by GLP-1 treatment is often accompanied by modest improvements in blood pressure and lipid profiles, which contributes to an overall improvement in cardiovascular risk factors and future health.

• Potential improvement in fatty liver —GLP-1 receptor agonists reduce liver fat in people with non-alcoholic fatty liver disease (NAFLD), a common condition in individuals with obesity and insulin resistance NAFLD is projected to be the number one cause of liver failure in the future. Dr. Dinesh comments that he has had a number of patients reverse early NAFLD and normalise liver tests after the weight loss that GLP-1 agonists confer. 

• Facilitating exercise by reducing osteoarthritic joint pain- Dr Dinesh comments that the weight loss from GLP-1 agonists often helps weight-related back and knee aches (osteoarthritis) which limit exercise and therefore facilitate the patient’s increase in activity and subsequent improvements in metabolism.

• Improvement in quality of life- Loss of weight may help some individuals in their self-confidence in their daily lives. It helps with the constant struggle and cravings that individuals experience in trying to reduce weight and therefore can reduce the stress these individuals experience in trying to improve their health. 

What are the side effects of GLP-1 injections?

GLP-1 receptor agonists are generally well tolerated, but like all medications, they can cause side effects — especially in the initial stages of treatment as the body adjusts to the hormonal changes or if a patient has not been counselled appropriately prior. Most side effects are mild and temporary, but it’s important to be aware of potential reactions and consult a healthcare provider if symptoms occur.

Here’s a breakdown of the most commonly reported side effects:

• Gastrointestinal symptoms — nausea, vomiting, diarrhoea, and constipation are the most frequently reported side effects. These symptoms tend to occur early in treatment and usually lessen over time. Gradual dose escalation under medical supervision can help minimise discomfort. Dr. Dinesh comments that he rarely sees this as he counsels his patients in appropriate portion control once injections start. This helps reduce nausea.

• Bloating or indigestion — slower gastric emptying can cause a feeling of fullness or bloating, especially after meals.

• Injection site reactions — mild redness, swelling, or itching at the site of injection may occur, though this is typically short-lived.

Less common but more serious side effects may include:

• Pancreatitis — in exceptionally rare cases, inflammation of the pancreas has been reported. Symptoms such as severe abdominal pain, nausea, or vomiting that doesn’t go away should be evaluated promptly.

• Gallbladder issues — some individuals may experience gallstones or inflammation of the gallbladder, particularly with rapid weight loss. Dr. Dinesh comments that it is unclear if this is due to the weight loss rather than the drug used but that it is important to note that patients need to seek medical attention if they have abdominal pain after meals especially in the right upper quadrant of the tummy.

• Thyroid concerns — animal studies have linked certain GLP-1 drugs with thyroid C-cell tumours, but this has not been confirmed in humans with studies failing to show a consistent link in humans. Nonetheless, individuals with a history of medullary thyroid carcinoma (a rare type of thyroid cancer) or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) are typically advised against using these medications.

It’s also essential to note that GLP-1 receptor agonists are not suitable for everyone. A full medical evaluation is required to determine suitability, especially for individuals with gastrointestinal disorders, kidney disease, or a history of pancreatitis.

Regular follow-up and medical supervision from an endocrinologist with expertise in this field can help ensure that treatment remains safe and effective, with any side effects promptly managed.

Who is an ideal candidate for GLP-1 injections in Singapore?

GLP-1 receptor agonists are prescribed as part of a medical weight management plan and are most suited for individuals who meet specific clinical criteria. These medications are not intended for casual or cosmetic weight loss, they are designed for people whose excess weight poses a risk to their health.

You may be considered an ideal candidate for GLP-1 therapy if:

• You have a body mass index (BMI) of 27.5 or higher (classified as obesity).

• You have a BMI of 23 or higher (overweight) and are living with weight-related health conditions, such as type 2 diabetes, high blood pressure, insulin resistance, dyslipidaemia, or obstructive sleep apnoea.

• You have previously struggled to lose weight through lifestyle modifications alone.

• You do not have a personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia syndrome type 2 (MEN 2).

• You are not pregnant or breastfeeding and do not plan to become pregnant during the treatment period.

At The Metabolic Clinic, all patients considering GLP-1 treatment undergo a thorough medical assessment to ensure the therapy is safe, appropriate, and aligned with their health goals. This process includes:

• A full review of your medical history, medications, and lifestyle habits.

• Baseline investigations such as blood tests to assess metabolic health, kidney and liver function, blood sugar levels, and cholesterol.

• A personalised treatment consultation to discuss expected outcomes, possible side effects, and how GLP-1 therapy fits into your overall care plan.

• Ongoing monitoring and follow-up, including regular weight tracking, dose adjustments, and support for nutrition and lifestyle improvements.

This comprehensive checkup ensures  that GLP-1 therapy is not only medically safe but also tailored to each individual’s unique needs, which can help maximise results while minimising risks.

How should I prepare myself for a GLP-1 injection session?

Preparing for a GLP-1 injection is simple, but a few steps can help ensure a smooth and comfortable experience, especially during the early phases of treatment:

• Eat light before your appointment — since GLP-1 injections slow down gastric emptying and may cause mild nausea, it's best to avoid heavy or greasy meals beforehand.

• Stay hydrated — drink plenty of water throughout the day to help your body adjust and to reduce the risk of dehydration, especially if you are prone to digestive side effects.

• Wear comfortable clothing — choose clothing that allows easy access to your upper arm, thigh, or abdomen, depending on the injection site recommended by your doctor (link to ‘About Us’ page).

• Avoid strenuous activity immediately after — while you can usually resume normal activities, it’s a good idea to keep the rest of your day light until you know how your body responds.

• Bring a list of current medications and medical history — this helps your healthcare provider monitor for any interactions or contraindications.

• Mentally prepare for mild side effects — knowing that some nausea or bloating may occur can reduce anxiety. Most side effects are temporary and tend to improve over time with proper dosing and support.

Your first session will also include clear guidance on how to administer injections (if applicable), what to expect in the coming days, and how to reach the care team for any concerns.

What results should I expect? 

GLP-1 receptor agonists have been shown in clinical studies to support meaningful and sustained weight loss when used alongside lifestyle changes such as improved diet, regular physical activity, and ongoing medical supervision. However, results can vary depending on individual factors including baseline weight, metabolic health, and adherence to the treatment plan.

Most individuals can expect the following outcomes:

• Gradual and steady weight loss — on average, patients lose about 10% to 15% of their starting body weight over several months. Weight reduction tends to occur progressively, with visible changes often beginning within the first 8 to 12 weeks of treatment.

• Improved appetite control — many people notice a significant decrease in food cravings and an increased sense of fullness after small meals, which makes it easier to maintain healthy eating habits.

• Better metabolic health — in addition to weight loss, many patients experience improved blood sugar levels, lower blood pressure, better cholesterol profiles, and reduced markers of insulin resistance, all of which contribute to long-term disease prevention.

• Boost in energy and wellbeing — as weight and metabolic markers improve, many individuals report increased energy, better sleep, and improved confidence and quality of life.

It’s important to remember that GLP-1 therapy is not a quick fix. The goal is sustainable, medically supported weight loss and better health over time. Ongoing support, regular follow-ups, and realistic expectations are key to achieving the best possible outcomes.

Summary 

GLP-1 receptor agonists offer a safe, medically supported path to weight loss for individuals who have struggled with traditional methods. By targeting the body’s natural hunger and satiety signals, these injections help reduce appetite, regulate blood sugar, and promote gradual, sustainable weight reduction. When paired with lifestyle changes and ongoing medical guidance, GLP-1 therapy can lead to significant improvements in overall metabolic health, including better blood pressure, cholesterol, and insulin sensitivity. 

If you are ready to explore a personalised approach to weight management that addresses the underlying biological factors—not just the symptoms—schedule a consultation with Dr Dinesh today to find out if GLP-1 treatment is right for you.

Frequently Asked Questions (FAQs) 

How long will I need to take GLP-1 injections?

The duration varies based on individual goals, change in lifestyle and response But for sustained results, individuals will need to prepare themselves for long-term therapy. 

What lifestyle changes should I make during GLP-1 therapy?

Adopting a balanced diet rich in lean proteins, vegetables, and whole grains is recommended. Portion-control is crucial. Regular physical activity with a mixture of resistance training to reduce muscle loss and cardio will be important. Stress management techniques like meditation can enhance the effectiveness of the treatment. ​

Will I regain weight after stopping GLP-1 injections?

Individuals may experience weight regain after discontinuing therapy as shown by all trials of GLP-1 medication. Maintaining healthy eating habits, regular exercise possibly facilitated by initial therapy can help sustain weight loss. ​

How quickly will I see results with GLP-1 injections?

Many patients begin to notice weight loss within the first 8 to 12 weeks of treatment. However, results can vary, and consistent lifestyle changes play a crucial role in the effectiveness of the therapy.​

What are the common side effects of GLP-1 injections?

Common side effects include nausea, vomiting, diarrhea, and constipation. These symptoms often diminish over time as your body adjusts to the medication.​

How are GLP-1 injections administered?

GLP-1 medications are typically administered via a subcutaneous injection, usually once a week. Your healthcare provider will guide you on proper injection techniques and schedules.​

Can I use GLP-1 injections if I have other medical conditions?

GLP-1 therapy may not be suitable for individuals with certain medical conditions, such as a history of pancreatitis or medullary thyroid cancer. A thorough medical evaluation is necessary to determine eligibility.​

Do I need to follow a specific diet while on GLP-1 therapy?

While there is no strict diet required, focusing on nutrient-dense foods and reducing intake of high-fat and high-sugar (high-calorie, less satiating) items can improve outcomes and minimize side effects.​

Are GLP-1 weight loss injections covered by insurance?

Coverage depends on your insurance plan and medical necessity. Some insurers cover these medications for individuals with obesity-related health conditions, while others may not. It’s essential to check with your provider for specific coverage details. ​