Medical Review by Jennie Stanford, MD, FAAFP, DABOM
Summary:
- Prescription weight loss medications can offer support in clinically indicated cases. GLP-1 options like Wegovy® and Ozempic®* can be especially effective when paired with lifestyle changes like diet and exercise.
- GLP-1 medications work by curbing appetite, slowing digestion, and improving insulin sensitivity. Studies have shown that they can lead to weight loss of 10-18%.
- Older drugs have more limitations. Medications like phentermine and orlistat show modest results, shorter treatment windows, and different side effects—some of which may be severe.
- Medical oversight is important if you take any drug for weight loss. Your healthcare provider can monitor your progress, manage side effects, and adjust your treatment plan for the best possible outcome.
Prescription medication can help with weight loss if it is right for you
Losing weight is a common goal for many people, but it can also be necessary for staying in good health. For people struggling with obesity or related conditions, prescription weight loss medications can offer much-needed support. But with so many options available, it’s important to understand which medications might work best for you.
This guide explores the different types of prescription weight loss medications, how they work, and why it’s important to check-in regularly with a qualified medical professional if you’re using them. Read on so you can have an informed conversation with your healthcare provider about creating an effective weight loss plan.
How GLP-1 medications are changing the world of weight loss
In recent years, GLP-1 receptor agonists have emerged as a promising option for weight loss in clinically indicated patients. These medications include:
- Wegovy®: a branded form of semaglutide, developed specifically to help overweight and obese adults manage their weight.
- Ozempic®: another formulation of semaglutide originally developed to manage type 2 diabetes, has also been used by providers off-label for weight loss.
How GLP-1 medications work
GLP-1 medications mimic a natural hormone called glucagon-like peptide-1 (GLP-1), which regulates appetite and blood sugar levels. By mimicking the action of this hormone, medications like Ozempic® and Wegovy® cause your insulin levels to rise and your blood sugar to go down—which has the following effects:
- Reducing appetite: These medications help you feel full sooner and for longer, which can reduce the number of calories you eat while they’re active in your system.
- Slowing digestion: By slowing a process called gastric emptying, these medications ensure that food stays in your stomach longer—which can help curb hunger.
- Improving insulin sensitivity: This isn’t directly related to weight loss—but since these medications can help your body manage blood sugar more effectively, they can also provide critical support for people with type 2 diabetes.
The effectiveness of GLP-1 medications for weight loss
Research has shown that GLP-1 medications can achieve significant results when prescribed to appropriate patients and used correctly. A clinical trial of 2.4mg semaglutide (which is the same amount as a typical Wegovy® dosage) showed an average reduction of body weight by 15.2% over a period of nearly two years.
Other research suggests that taking this amount of semaglutide once per week could cause weight loss of anywhere from 10-18%. It also shows that this weight loss is more sustainable than the weight loss achieved with other available medications, and that it can lead to health and quality of life improvements as well by reducing the risk of the physical and mental health problems that often come with obesity.
Limitations of conventional medications
Before GLP-1 medications, weight loss treatments like phentermine and orlistat were widely prescribed. While these medications still have a place in some treatment plans, they’ve taken a backseat due to their limitations.
Why older medications are less popular
The popularity of GLP-1 medications over older weight loss drugs may be explained by any of the following factors:
- Lower efficacy: Compared to GLP-1 medications, older drugs often result in more modest weight loss. For example, studies show phentermine typically leads to weight loss of around 5%, with similar results for orlistat.
- Shorter window of use: Older weight loss medications are not intended for long-term use like semaglutide is. Studies on phentermine focus on its effectiveness for up to 12 weeks, while studies on orlistat measure its efficacy for up to 24 weeks—while semaglutide has been shown to have effects for years.
- Side effects: Some of the side effects associated with phentermine include increasing your heart rate by up to 20 beats per minute and the risk of mood disorders or cognitive disturbances.
- Medications like phentermine, a stimulant, carry a risk of increased heart rate, insomnia, and anxiety. Orlistat, which blocks fat absorption, can cause unpleasant gastrointestinal side effects, like oily stools and cramping.
Why medical oversight matters
While prescription weight loss medications can help people lose weight in clinically indicated cases, they’re not for everyone. Even if your healthcare provider prescribes you medication for weight loss, you will need to check in with them for medical guidance to ensure maximum safety and effectiveness during your treatment.
When to contact your healthcare provider
There are several circumstances when you should reach out to your healthcare provider if you’re taking prescription weight loss medications. These can vary depending on what medication you’re taking.
For GLP-1 medications
Talk to your healthcare provider if you have any unusual problems (including severe or persistent side effects) while using the medication. You will also need to keep any follow-up appointments your provider asks you to schedule, and may need to measure your own blood sugar levels at home so that you can report the results.
For Phentermine
Contact your healthcare provider if you experience ongoing or severe side effects, such as dry mouth, unpleasant tastes, or diarrhea. You should also contact a medical professional as soon as possible if you notice serious problems like a sudden increase in blood pressure or heart palpitations.
For Orlistat
Consult a healthcare provider if you experience ongoing or severe side effects, like spotting, gas, problems with bowel movements, headaches, and anxiety. You should also get help if you notice potential signs of more serious problems—like skin conditions, or trouble breathing or swallowing.
A healthcare provider can help you manage these side effects and decide if adjustments to your treatment plan are needed.
Personalizing your treatment
Checking in with a healthcare provider can help you create a personalized weight loss plan. A qualified medical professional can help you by:
- Identifying a healthy weight for you
- Working with you to set realistic and achievable weight loss goals
- Providing recommendations on how to lose weight
- Prescribing or adjusting your dosage of weight loss medications in clinically indicated cases
Combining medication with lifestyle changes
Prescription medications can often be supported by broader lifestyle changes. GLP-1 medications, in particular, are most effective for weight management when combined with a healthy diet and exercise.
Other forms of support may help with weight loss as well. Here are some examples:
- Dietary improvements: A balanced, calorie-conscious diet is critical for achieving and maintaining weight loss. Your provider might make recommendations based on the Dietary Guidelines for Americans, which focuses on eating nutrient-dense foods like vegetables, fruits, whole grains, and plenty of protein.
- Exercise: Regular physical activity supports weight loss and offers additional health benefits like improved cardiovascular fitness.
- Behavioral support: Therapy or counseling may help address emotional or psychological factors contributing to weight gain. For example, cognitive behavioral therapy (CBT) has not been shown to directly cause weight loss—but it has been recognized as an effective way to address the binge eating that often contributes to obesity.
Learn more about using prescription weight loss medications responsibly
Prescription weight loss medications—particularly GLP-1 options like Wegovy® and Ozempic®—have transformed how healthcare providers approach weight management. Combining these medications with lifestyle changes and professional guidance can lead to meaningful and lasting results in many people.
If you’re considering weight loss medications, consulting a healthcare provider is the first step. Lemonaid Health offers convenient online consultations with licensed professionals who can help you explore your options and develop a comprehensive treatment plan that may include medication if clinically indicated.
Get started today and take the next step on your weight loss journey. A healthier you is within reach.
Ozempic® and Wegovy® are registered trademarks of Novo Nordisk A/S.
*Ozempic is approved for the treatment of Type 2 Diabetes, but may, in a provider’s independent discretion be prescribed off label for weight loss.
