Comprehensive Guide to Weight Loss Medications in Singapore

Tackling Weight Gain: Effective Medication Strategies in Singapore

Singapore's fast-paced lifestyle often contributes to challenges such as weight gain, primarily driven by sedentary habits, unhealthy dietary choices, and genetic predispositions. In response, a variety of oral weight loss medications, each with unique methods to combat obesity, have been approved and become popular solutions for those dealing with obesity or related health issues. 

This in-depth article explores three widely used types of weight loss pills in Singapore: Rybelsus, Orlistat, and Phentermine, delving into their mechanisms, benefits, and suitability.

Rybelsus: Improving Appetite Control

Rybelsus stands out as a significant development in weight loss pharmacology. It harnesses the body's natural mechanisms to regulate appetite. The primary component, Semaglutide, is adept at mimicking hormones responsible for signaling fullness, thus diminishing the desire to overeat. This leads to a more manageable appetite and easier calorie control, without the discomfort of frequent hunger. In Singapore's health circles, Rybelsus is popular for its progressive approach towards fostering long-term weight loss.

Learn more about Rybelsus here

Orlistat (Xenical, Alli): Fat Absorption Reduction

Orlistat, available as Xenical and Alli, differentiates itself by targeting fat absorption in the digestive process. This drug effectively blocks a substantial portion of dietary fat from being absorbed and digested, leading to its elimination from the body. When paired with a low-calorie diet, Orlistat is a powerful tool for achieving gradual, sustainable weight loss, making it another popular choice for long-term weight management strategies.

Phentermine (Panbesy, Duromine, Qsymia): Appetite Suppression

Phentermine, recognized under brand names such as Panbesy, Duromine, and Qsymia, is known for its appetite suppressing properties. It works by acting on central nervous system neurotransmitters, reducing hunger cravings and enhancing satiety. Often prescribed for short-term use, Phentermine forms a key part of comprehensive weight management programs that include regular exercise and a balanced diet. Its effectiveness in quickly reducing appetite makes it a popular choice for those seeking results in their weight loss journey.

These medications, each with their distinct approach, provide a range of solutions for individuals seeking medical assistance in weight management.

However, it's essential to consult with a doctor to identify the most suitable option based on personal health profiles and specific needs.

In the upcoming sections, we will provide a more detailed analysis of each medication, covering their effectiveness, suitability, potential side effects, and key considerations to bear in mind before embarking on any weight loss medication regimen in Singapore. 

In-Depth Examination of Weight Loss Medications


Mechanism of Action: 

Rybelsus, containing Semaglutide, operates by replicating the effects of GLP-1 (glucagon-like peptide-1), a hormone pivotal in regulating appetite. Semaglutide stimulates GLP-1 receptors in the brain, heightening feelings of fullness and satisfaction. This process leads to a gradual and natural reduction in calorie intake as the body adapts to lower food requirements for satiety.

Dosage and Administration: 

The standard procedure for initiating Rybelsus treatment begins with a lower dose, progressively increasing it to ensure tolerability. Typically, the initial dose is 3 mg daily, with possible escalation to 7 mg and even 14 mg based on patient response and tolerance. Consistency in daily intake, preferably on an empty stomach, enhances its effectiveness.

Effectiveness and Clinical Trials Data: 

Rybelsus's effectiveness in weight management has been substantiated in numerous clinical trials. Over a 68-week study, participants using Rybelsus witnessed an average weight loss ranging from 5% to 10% of their initial body weight. Some individuals achieved higher weight reductions, particularly when complemented with lifestyle adjustments like dietary modifications and regular exercise. 

Another notable trial highlighted that individuals on a higher Rybelsus dose (14 mg) experienced an average 7% body weight reduction over six months, compared to those not on the medication. It is essential to note that outcomes may vary based on factors such as baseline weight, adherence to the medication regimen, and lifestyle changes.

Side Effects and Precautions: 

Commonly reported side effects of Rybelsus encompass gastrointestinal symptoms like nausea, stomach pain, and diarrhea. These effects are typically more pronounced at the beginning of treatment and often diminish over time. Individuals with specific health concerns, such as a history of pancreatitis or diabetic complications, should consult their healthcare provider to assess Rybelsus's suitability for their condition.

Orlistat (Xenical, Alli)

Mechanism of Action: 

Orlistat stands out among weight loss medications by operating directly within the gastrointestinal tract, inhibiting the action of lipase enzymes responsible for breaking down dietary fats. This inhibition prevents approximately 25-30% of fat in a meal from being absorbed by the body, leading to a reduced calorie intake from fats.

Dosage and Administration: 

Typically, Orlistat is administered through 120 mg capsules taken with each primary meal (up to three times daily). Notably, its action is limited to the dietary fat consumed. To maximize its effectiveness, it is advisable to follow a nutritionally balanced, mildly reduced-calorie diet comprising approximately 30% of calories from fat. Additionally, distributing daily fat, carbohydrate, and protein intake over three main meals is recommended.


Clinical trials have demonstrated the effectiveness of Orlistat in enhancing weight loss efforts. Research indicates that individuals using Orlistat in conjunction with lifestyle modifications can expect to lose about 5-10% of their initial body weight within six months. This weight loss is notably greater than that achieved through diet and exercise alone.

Side Effects and Precautions: 

Common side effects associated with Orlistat relate to its fat-blocking mechanism, including oily spotting, flatulence with discharge, urgent bowel movements, and fatty or oily stools. These effects are generally mild and temporary, particularly when adhering to the recommended diet with roughly 30% of calories from fat. Caution is advised for individuals with a history of specific medical conditions like malabsorption syndrome or cholestasis.

Phentermine (Panbesy, Duromine, Qsymia)

Mechanism of Action: 

Phentermine, well-known for its role in weight loss, primarily acts as an appetite suppressant by influencing the central nervous system. It reduces hunger and aids in controlling calorie intake by stimulating the release of brain chemicals that modulate the brain's appetite control center, leading to decreased appetite and increased fullness.

Brand Names in Singapore: 

In Singapore, Phentermine is available under various brand names, including Panbesy, Duromine, and Qsymia. These brands share Phentermine as the active ingredient but may vary in formulation or dosage.

Dosage and Administration: 

Phentermine dosage varies depending on the specific brand and individual prescription. Typically, it is taken once daily, either before breakfast or 1 to 2 hours after breakfast. Consistency in daily administration at the same time is critical for effectiveness. Phentermine is generally recommended for short-term use, often spanning a few weeks to a few months, as prescribed by your doctor.

Clinical Efficacy and Study Results: 

Phentermine's effectiveness in weight management is supported by multiple clinical trials. For instance, a study published in the "Journal of the American Medical Association" reported that participants combining Phentermine with diet and exercise achieved an average weight loss of approximately 5% of their initial body weight over 12 weeks. 

Another study highlighted that, over a 3 to 6-month period, patients on Phentermine lost more weight on average than those on placebo, with some individuals experiencing up to a 10% reduction in body weight. It is noteworthy that Phentermine's weight loss effects are typically more prominent in the initial treatment phases and may plateau over time. The medication is generally recommended as part of a comprehensive weight management program encompassing lifestyle, dietary, and behavioral modifications.

Side Effects and Precautions: 

Common side effects associated with Phentermine include an increased heart rate, dry mouth, restlessness, and potential insomnia. Due to its stimulant effects, individuals with a history of cardiovascular disease, hyperthyroidism, or glaucoma are advised against its use. A thorough consultation with your doctor is crucial to assess its suitability and discuss potential health risks.

Comprehensive Comparison of Weight Loss Medications: Rybelsus, Orlistat, and Phentermine

When exploring oral weight loss medications, understanding each option's mechanism, benefits, and potential drawbacks is crucial. This section provides an easy-to-read comparison of Rybelsus, Orlistat, and Phentermine, focusing on their distinct features and considerations for effective weight management.

Mechanism of Action

Rybelsus: Enhances the body's inherent appetite regulation mechanism, promoting a longer feeling of fullness.

Orlistat: Inhibits the absorption of dietary fats, thereby reducing fat-derived calorie intake.

Phentermine: Actively suppresses appetite through its influence on brain neurotransmitters, aiding in appetite control.

Target User Profile

Rybelsus: Suitable for individuals facing challenges with overeating or persistent hunger.

Orlistat: Ideal for those who consume diets high in fat and are committed to following a reduced-calorie, controlled diet.

Phentermine: Recommended for individuals seeking help in controlling appetite, particularly beneficial at the beginning of a weight loss program.


Rybelsus: Typically results in moderate weight loss, with increased effectiveness when combined with lifestyle modifications.

Orlistat: Can lead to significant weight loss over time, particularly effective with adherence to a controlled diet.

Phentermine: Known for providing noticeable weight loss results in the short term, often observed within the initial stages of treatment.

Side Effects

Rybelsus: Common side effects include gastrointestinal issues like nausea and stomach pain, which are often more noticeable at the start of treatment.

Orlistat: May cause gastrointestinal side effects, particularly if the diet contains excess fat.

Phentermine: Common side effects include increased heart rate, dry mouth, restlessness, and potential insomnia, emphasizing the need for careful monitoring and medical supervision during use.

Duration of Use

Rybelsus: Suitable for longer-term use as part of an extensive weight management plan, aligning with ongoing lifestyle changes.

Orlistat: Also appropriate for long-term use, especially for individuals committed to maintaining a low-fat diet.

Phentermine: Generally prescribed for short-term use, due to its stimulant properties.

Best Fit Consideration

Rybelsus: Optimal for those seeking a sustainable, long-term solution that complements the body’s natural appetite control mechanisms.

Orlistat: Best suited for individuals focused on managing dietary fat intake and adhering to a low calorie-controlled diet.

Phentermine: Ideal for those requiring short term assistance with appetite suppression, often as part of a comprehensive weight loss plan that includes dietary and lifestyle changes.

Making an Informed Decision

Selecting the most appropriate weight loss medication involves a thorough evaluation of individual health needs, medical history, lifestyle habits, and specific weight loss objectives. Consulting with your doctor is essential to determine which medication aligns best with your unique health situation. 

It's important to remember that weight loss pills are most effective when integrated into a holistic approach to weight management, which includes a balanced diet, regular physical activity, and positive lifestyle changes.

Exploring Injectable Weight Loss Options: Saxenda, Ozempic, and Wegovy

For those in search of more powerful weight loss solutions, injectable medications present a promising alternative, potentially offering enhanced effectiveness compared to oral weight loss pills. In the domain of weight management, Saxenda, Ozempic, and Wegovy are prominent as injectable choices, each with unique features and specific uses.


Saxenda, containing liraglutide, is primarily utilized for weight management in adults and children over 12 who are overweight or obese. It functions by mimicking a naturally occurring hormone that regulates appetite, thereby reducing hunger and aiding in calorie control. While Saxenda is particularly effective for weight loss, it's noteworthy that it doesn't primarily focus on blood sugar regulation, making it a preferred option for individuals without diabetes. Its use is recommended alongside a lifestyle that includes a balanced diet and regular physical activity.

Learn more about Saxenda here


Ozempic, with semaglutide as its active ingredient, is initially developed for managing Type 2 Diabetes. However, it also exhibits properties that can aid in weight loss. By improving blood sugar control and affecting appetite centers in the brain, Ozempic not only assists in diabetes management but can also contribute to weight reduction. It's important to note that while Ozempic can support weight loss, it's primarily prescribed for diabetes care.

Learn more about Ozempic here


Wegovy, also containing semaglutide, is specifically approved for chronic weight management. It's suitable for overweight or obese adults who have weight-related health issues such as high blood pressure, high cholesterol, or Type 2 Diabetes. Wegovy functions similarly to Ozempic in controlling appetite but is available in higher doses specifically designed for weight loss. It's most effective when used in conjunction with a reduced-calorie diet and increased physical activity.

Learn more about Wegovy here

Get Professional Advice

Book a consultation now with Dr Edwin to learn how your skin goals can be achieved.

Leave us your name, contact details and we will be in touch soon!
Contact us
linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram