Weight Loss
33 min read
Written by Douglas Helm
Published: Feb 28, 2024
Medically Reviewed by Goldina Erowele, PharmD, MBA
Exploring weight loss options? You may have come across the term glucagon-like peptide 1 (GLP-1) or GLP-1 agonist medications in your research. Most GLP-1 agonists help control blood sugar levels in individuals with type 2 diabetes. But some are Food and Drug Administration (FDA)-approved as prescription weight management medications.
In this article, we compare 10 GLP-1 agonist medications. We give you insight into how they work, their effectiveness for weight loss, and potential side effects. By the end of this article, you’ll have the knowledge and confidence to talk about these medications with your healthcare provider. Together, you and your provider can determine if one is right for you and which is the best prescription weight loss pill or medication for your needs. Let’s dive in.
Our body naturally produces a hormone called glucagon-like peptide-1 or GLP-1 for short. This hormone is made by our small intestine and plays an important role in several bodily functions. GLP-1 agonists, also known as GLP-1 receptor agonists, are a class of medication that works by mimicking the action of GLP-1. Some of GLP-1’s primary roles include:
According to an article published by StatPearl Publishing, these effects of GLP-1 help promote weight loss. In a nutshell, these medications help manage hunger, cause delayed gastric emptying, and decrease appetite, which helps you control the amount of food you eat.
The combined effect is sustainable and safe weight loss for people who take a GLP-1 agonist medication under medical supervision, according to a clinical review of GLP-1 receptor agonists published in Drugs in Context.
Let’s take a closer look at some of these benefits.
The benefits of GLP-1 agonists are similar because they all mimic GLP-1. The amount of benefit varies though based on which GLP-1 weight loss medication you take. Each has a different dose and some also include other mechanisms. Some of the most common benefits include the following.
Many GLP-1 agonist medications are approved for type 2 diabetes. They help control blood sugar levels, which can help with diabetes. Remember, GLP-1 triggers insulin secretion and blocks the release of glucagon. This helps lower blood sugar and signals the body to burn fat, rather than store it. Many also lead to weight loss but prescribing those only approved by the FDA for type 2 diabetes for weight loss is an off-label use.
Some GLP-1 agonists are specifically manufactured and FDA-approved and prescribed for weight loss. These medications are identical or similar to those approved to control blood sugar for people with type 2 diabetes. They are used to help reduce appetite, increase feelings of fullness, and slow digestion. This combination helps individuals control portions and calorie intake, leading to weight loss.
There are several GLP-1 agonist medications on the market. Most GLP-1 agonists are available as injections. Today, only Rybelsus is available as an oral pill, which is taken by mouth. Talk to your healthcare provider about which one may be right for you.
Medication | Potential benefits | Approved use and who can take it | Potential side effects |
Wegovy (semaglutide) | Body weight loss of up to 14.9% (trial data) | Approved for weight loss when combined with a reduced-calorie meal plan and increased physical activity for: Adults with body mass index (BMI) over 30 Adults with a BMI equal to or more than 27 with a weight-related health condition Children 12 or older at or above the 95th percentile for their sex and age | Nausea, diarrhea, stomach pain, upset stomach, dizziness, bloating, gas, fatigue, headache, vomiting, constipation, heartburn, runny nose, and/or sore throat* |
Zepbound (tirzepatide) | Body weight loss of up to 20.9% (data) | Approved for chronic weight loss management when combined with a reduced-calorie diet and increased physical activity for: Adults with a BMI over 30 Adults with a BMI equal to or more than 27 with a weight-related health condition | Nausea, diarrhea, vomiting, constipation, stomach pain, indigestion, injection site reactions, feeling tired, allergic reactions, belching, hair loss, and/or heartburn* |
Saxenda (liraglutide) | Body weight loss of up to 10% (trial data) | Approved for weight loss for: Adults with a BMI over 30 Adults with a BMI equal to or more than 27 with a weight-related health condition Children 12–17 that weigh more than 132 pounds Should be used with a reduced calorie diet and increased physical activity | Nausea, diarrhea, constipation, vomiting, injection site reaction, low blood sugar, headache, fatigue, dizziness, stomach pain, and/or changes in enzyme levels in the blood* |
Ozempic (semaglutide) | 1.9 to 2.2% reduction in A1C Weight loss of 12 to 15 lbs (study) | Approved for: Adults with type 2 diabetes Adults with type 2 diabetes and known heart disease Should be used with diet and exercise | Nausea, vomiting, diarrhea, stomach pain, and/or constipation* |
Rybelsus (semaglutide) | 0.7 to 1.9% reduction in A1C 5 to 8 lbs of weight loss (study) | Approved for: Adults with type 2 diabetes Should be used with diet and exercise | Nausea, stomach pain, diarrhea, decreased appetite, vomiting, and/or constipation* |
Mounjaro (tirzepatide) | 2 to 2.3% reduction in A1C 17 to 25 lbs of weight loss (trial data) | Approved for: Adults with type 2 diabetes Should be used with diet and exercise | Nausea, diarrhea, decreased appetite, vomiting, constipation, indigestion, and/or stomach pain* |
Victoza (liraglutide) | 1.0 to 1.5% reduction in A1C Average weight loss of 6.2 lbs (study) | Approved for: Adults with type 2 diabetes Adults with type 2 diabetes and known heart disease Children 10 or older with type 2 diabetes Should be used with diet and exercise | Nausea, diarrhea, vomiting, decreased appetite, indigestion, and/or constipation* |
Trulicity (dulaglutide) | 1.0 to 1.6% reduction in A1C Weight loss of 1.7 to 6.4 lbs (study) | Approved for: Adults with type 2 diabetes Adults with type 2 diabetes and heart disease or multiple cardiovascular risk factors Children 10 or older with type 2 diabetes Should be used with diet and exercise | Nausea, diarrhea, vomiting, stomach pain, decreased appetite, indigestion, and/or fatigue* |
Bydureon BCise (exenatide extended release) | 1.1 to 1.4% reduction in A1C Average weight loss of 3 lbs (study) | Approved for: Adults with type 2 diabetes Children 10 or older with type 2 diabetes Should be used with diet and exercise | Nausea, bump at the injection site* |
Byetta (exenatide) | 0.7 to 0.9% reduction in A1C Average weight loss of 6 to 6.4 lbs (study) | Approved for: Adults with type 2 diabetes | Nausea, indigestion, vomiting, diarrhea, and/or constipation* |
*For full details on both common and serious side effects see the medication guide or talk to your healthcare provider or pharmacist.
Let’s take a closer look at each of these medications.
Wegovy is a GLP-1 agonist with the active ingredient semaglutide. You may notice that this is the same active ingredient as Ozempic. While these two both contain semaglutide, they are approved for different uses. Learn more about Ozempic vs Wegovy.
Approved for. Wegovy is a medication approved for weight loss when combined with a reduced-calorie meal plan and increased physical activity. Adults with a body mass index (BMI) over 30 can take Wegovy. Adults with a BMI of 27 or more can take it if they have a known weight-related health condition. BMI is a measure of your body fat, and your risk for certain diseases is higher with a higher BMI. Children 12 or older can take it if they are at or above the 95th weight percentile for their sex and age.
Data on effectiveness. A 68-week clinical trial of Wegovy was conducted with 1,961 adults. Participants were obese or had excess weight along with a weight-related medical condition. In the study, adults taking Wegovy lost an average of 35 pounds, or 14.9% of their body weight. Participants taking a placebo lost an average of 6 pounds, or 2.5% of their body weight. Both groups were instructed to follow a reduced-calorie meal plan and exercise program.
Oral/injection. Wegovy is an injectable medication taken under the skin in the stomach area (abdomen), upper leg (thigh), or upper arm and per the instructions of a healthcare provider.
Dosage. Wegovy is injected under the skin once a week. The starting dose for Wegovy is 0.25 milligrams once a week. This dose is gradually increased until reaching a maintenance dose of either 1.7 milligrams or 2.4 milligrams, depending on your provider’s instructions.
Side effects. Common side effects of Wegovy are nausea, diarrhea, stomach pain, upset stomach, dizziness, bloating, gas, fatigue, headache, vomiting, constipation, heartburn, runny nose, and/or sore throat. For full details on common and serious side effects see the Wegovy medication guide or talk to your healthcare provider or pharmacist.
Zepbound is a GLP-1 agonist with the active ingredient tirzepatide. It has the same active ingredient and is the medication as Mounjaro. It’s simply marketed under a different brand name. Where Ozempic and Wegovy are similar, but not identical or interchangeable, Zepbound and Moujaro are identical. The exception is that Zepbound is FDA-approved to treat excess weight and obesity and Mounjaro is FDA-approved to treat type 2 diabetes.
Approved for. Zepbound is a medication approved for weight loss when combined with a reduced-calorie diet and increased physical activity. Adults with a BMI over 30 can take Zepbound. It can also be taken by adults with a BMI equal to or more than 27 if they have a known weight-related condition.
Data on effectiveness. An extended clinical trial was conducted with Zepbound. Participants included adults with diabetes and adults without diabetes. The study found that participants who dieted and exercised achieved sustained weight loss on 5-milligram, 10-milligram, and 15-milligram doses of Zepbound. Adults without diabetes saw average weight loss of 15% to 20.9% depending on dosage, compared to 3.1% for people on a placebo. Adults with diabetes saw 12.8% to 14.7% depending on dosage, compared to 3.2% for those on a placebo.
Oral/injection. Zepbound is an injectable medication taken under the skin.
Dosage. Zepbound is injected once a week. The starting dose for Zepbound is 2.5 milligrams. The dose is increased to 5 milligrams after four weeks. After another four weeks, your provider may increase your dosage again to 7.5 milligrams. Some people will use 5 milligrams for their maintenance dose.
Side effects. Common side effects of Zepbound include nausea, diarrhea, vomiting, constipation, stomach pain, indigestion, injection site reactions, feeling tired, allergic reactions, belching, hair loss, and/or heartburn. For full details on common and serious side effects see the Zepbound medication guide or talk to your healthcare provider or pharmacist.
Saxenda is a GLP-1 agonist with the active ingredient liraglutide. Saxenda uses the same active ingredient as Victoza, which is approved for type 2 diabetes. Saxenda is taken at a higher dose and approved for weight loss.
Approved for. Saxenda is a medication approved for weight loss. It should be used with a reduced calorie diet and increased physical activity. It’s approved for use in adults with a BMI over 30. Adults with a BMI equal to more than 27 can take Saxenda if they have a known weight-related condition. Saxenda is also approved for children 12 or older who are obese and over 132 pounds.
Data on effectiveness. In clinical trials, 85% of participants taking Saxenda lost weight. Participants in the study were also counseled on following a reduced-calorie diet and doing physical activity. A long-term study of Saxenda found that 56% of participants achieved significant weight loss after one year. 3 years later, half of these participants maintained their weight loss. Additionally, patients with a BMI over 30 or a BMI equal or more than 27 lost an average of 8% of their body weight after 56 weeks when combining daily liraglutide with lifestyle advice. This was 5.3% more than the placebo group.
Oral/injection. Saxenda is an injectable medication taken under the skin.
Dosage. Saxenda is injected once a day. The starting dosage of Saxenda is 0.6 milligrams. The dose is increased by 0.6 milligrams each week until the maintenance dose of 3.0 milligrams is reached.
Side effects. Common side effects of Saxenda include nausea, diarrhea, constipation, vomiting, injection site reaction, low blood sugar, headache, fatigue, dizziness, stomach pain, and changes in enzyme levels in the blood. For full details on common and serious side effects see the Saxenda medication guide or talk to your healthcare provider or pharmacist.
Ozempic is a GLP-1 agonist with the active ingredient semaglutide. This is the same active ingredient as Wegovy, but Ozempic is approved for type 2 diabetes and is not interchangeable with Wegovy.
Approved for. Ozempic is a medication approved for adults with type 2 diabetes. It’s prescribed to improve blood sugar levels when used with diet and exercise. Another approved use for Ozempic is to reduce the risk of major cardiovascular disease, like heart attack or stroke, in adults with type 2 diabetes with known heart disease.
Data on effectiveness. In clinical trials, a majority of adults with type 2 diabetes saw an A1C reduction of 1.9 to 2.2% —and to 7% or lower — in 40 weeks. A1C is a test that measures your average blood sugar over the past three months. The American Diabetes Association recommends an A1C of less than 7% for adults with type 2 diabetes. Although Ozempic is not a weight loss medication, adults in the same studies lost an average of 12 to 15 pounds.
Oral/injection. Ozempic is an injectable medication taken under the skin in the stomach area (abdomen), upper leg (thigh), or upper arm per the instructions of a healthcare provider.
Dosage. Ozempic is injected once weekly. The starting dose is 0.25 milligrams for 4 weeks before increasing the dosage to 0.5 milligrams. Depending on your needs, you may work up to 1.0 or 2.0 milligrams a week.
Side effects. Common side effects of Ozempic include nausea, vomiting, diarrhea, stomach pain, and/or constipation. For full details on common and serious side effects see the Ozempic medication guide or talk to your healthcare provider or pharmacist.
Rybelsus is a GLP-1 agonist with the active ingredient is semaglutide, like Ozempic and Wegovy. But it’s taken as a daily oral pill instead of an injection. Unlike many GLP-1 agonist medications, Rybelsus is an oral medication.
Approved for. Rybelsus is approved for adults with type 2 diabetes and combined with diet and exercise.
Data on effectiveness. A 6-month study of Rybelsus found an average drop of 1 to 1.3% A1C in adults with a starting A1C of 8.3%. While Rybelsus is not a weight loss medication, the same study saw participants weighing over 200 pounds lose an average of 5 to 8 pounds.
Oral/injection. Rybelsus is an oral medication.
Dosage. Rybelsus is a once-daily pill. It comes in 7.0 milligrams and 14 milligrams tablets. Make sure to take Rybelsus as instructed by your healthcare provider.
Side effects. Common side effects of Rybelsus are nausea, stomach pain, diarrhea, decreased appetite, vomiting, and/or constipation. For full details on common and serious side effects see the Rybelsus medication guide or talk to your healthcare provider or pharmacist.
Mounjaro is a GLP-1 agonist with the active ingredient tirzepatide. Mounjaro and Zepbound are the same medication with different names and different approved uses. Mounjaro is approved for type 2 diabetes while Zepbound is an approved weight loss medication.
Approved for. Mounjaro is a medication approved for adults with type 2 diabetes and should be used with diet and exercise.
Data on effectiveness. A 40-week study of Mounjaro tested the drug with participants with type 2 diabetes. Participants had an average reduction in A1C of 2 to 2.3% depending on dosage. While Mounjaro is not a weight loss drug, the same study participants had an average weight loss of 17 to 25 pounds.
Oral/injection. Mounjaro is an injectable medication taken under the skin.
Dosage. Mounjaro is injected once weekly. The starting dose is 2.5 milligrams for 4 weeks. After, you increase to 5.0 milligrams per week. You and your provider will determine if your maintenance dose should be more than 5.0 milligrams. Maintenance doses can be up to 15 milligrams per week.
Side effects. Common side effects of Mounjaro include nausea, diarrhea, decreased appetite, vomiting, constipation, indigestion, and/or stomach pain. For full details on common and serious side effects see the Mounjaro medication guide or talk to your healthcare provider or pharmacist.
Victoza is a GLP-1 agonist with the active ingredient liraglutide. This is the same active ingredient as Saxenda, but Victoza is approved for type 2 diabetes and is not a weight loss medication.
Approved for. Victoza is a medication approved for adults with type 2 diabetes. It’s also approved for children 10 years of age or older with type 2 diabetes. Another approved use for Victoza is to reduce the risk of major cardiovascular disease, like heart attack or stroke, in adults with type 2 diabetes with known heart disease. It should be used with diet and exercise.
Data on effectiveness. Clinical trials found Victoza helped adults lower A1C by an average of 1 to 1.5%. While Victoza is not a weight loss medication, a study found that adults lost an average of up to 6.2 pounds when Victoza was used with metformin, another prescription medication for type 2 diabetes.
Oral/injection. Victoza is an injectable medication taken under the skin in the stomach area (abdomen), upper leg (thigh), or upper arm per the instructions of a healthcare provider.
Dosage. Victoza is injected once daily. The starting dose is 0.6 milligrams daily for a week. After one week, the dose is increased to 1.2 milligrams daily. Depending on your needs, your provider may prescribe a maximum daily dose of up to 1.8 milligrams.
Side effects. Common side effects of Victoza include nausea, diarrhea, vomiting, decreased appetite, indigestion, and/or constipation. For full details on common and serious side effects see the Victoza medication guide or talk to your healthcare provider or pharmacist.
Trulicity is a GLP-1 agonist with the active ingredient dulaglutide. Dulaglutide doesn’t have a medication equivalent approved for weight loss, unlike many of the type 2 diabetes medications on this list. While weight loss is sometimes a benefit of taking dulaglutide, it is not a weight loss medication.
Approved for. Trulicity is a medication approved for adults with type 2 diabetes. It’s also approved for children 10 years of age or older with type 2 diabetes. Another approved use for Trulicity is to reduce the risk of major cardiovascular disease, like heart attack or stroke, in adults with type 2 diabetes with known heart disease or multiple risk factors for heart disease. It should be with diet and exercise.
Data on effectiveness. Clinical studies on Trulicity found that it reduced A1C by 1.3 to 1.6%. While Trulicity is not a weight loss medication, study participants lost from 1.7 to 6.4 pounds.
Oral/injection. Trulicity is an injectable medication taken under the skin in the stomach area (abdomen), upper leg (thigh), or upper arm per the instructions of a healthcare provider.
Dosage. Trulicity is injected once a week. The starting dose is 0.75 milligrams for 4 weeks. Dosage can increase in 1.5 milligrams increments after 4 weeks on the previous dosage. The maximum maintenance dose is 4.5 milligrams weekly.
Side effects. Common side effects of Trulicity include nausea, diarrhea, vomiting, stomach pain, decreased appetite, indigestion, and/or fatigue. For full details on common and serious side effects see the Trulicity medication guide or talk to your healthcare provider or pharmacist.
Bydureon BCise is a GLP-1 agonist with the active ingredient extended-release exenatide.
Approved for. Bydureon BCise is a medication approved for adults with type 2 diabetes. It’s also approved for children 10 years of age or older with type 2 diabetes. It is not an approved weight loss medication.
Data on effectiveness. In clinical studies with adults with type 2 diabetes, Bydureon BCise lowered A1C by an average of 1.1 to 1.4% from an average starting A1C of 8.4 to 8.5%. While Bydureon BCise is not a weight loss medication, study participants lost an average of 3 pounds.
Oral/injection. Bydureon BCise is an injectable medication taken under the skin.
Dosage. Bydureon BCise is injected once weekly. The dose is 2.0 milligrams.
Side effects. Common side effects of Bydureon BCise are nausea and/or a bump at the injection site. For full details on common and serious side effects see the Bydureon BCise medication guide or talk to your healthcare provider or pharmacist.
Byetta is a GLP-1 agonist with the active ingredient exenatide. Unlike Bydureon BCise, which is an extended-release medication, Byetta is an immediate-release formulation of exenatide.
Approved for. Byetta is a medication approved for adults with type 2 diabetes.
Data on effectiveness. Clinical studies of Byetta on participants with type 2 diabetes found that average A1C was reduced by 0.7% to 0.9%. While Byetta is not a weight loss medication, participants lost an average of 6 to 6.4 pounds.
Oral/injection. Byetta is an injectable medication taken under the skin.
Dosage. Byetta is injected twice daily. The starting dose of Byetta is 5.0 micrograms twice per day. The dose may be increased to 10 micrograms twice per day, depending on your needs.
Side effects. Common side effects of Byetta include nausea, indigestion, vomiting, diarrhea, and/or constipation. For full details on common and serious side effects see the Byetta medication guide or talk to your healthcare provider or pharmacist.(The guide linked here is the AstraZeneca brand of Byetta. Amylin also makes Byetta.)
Like any medication, there are potential side effects to taking GLP-1 agonists. The most common side effects include:
Side effects are usually mild to moderate. They’re also more likely when you’re first starting medication or if you increase your dosage. As your body adjusts, you may see side effects subside. But, keep your healthcare provider updated on any side effects you experience.
There’s also a risk of severe side effects when using GLP-1 drugs. These side effects are much rarer and include:
Seek immediate medical attention if you experience any severe symptoms on a GLP-1 or other medication.
It’s important to note that not everyone can experience side effects. Your individual experience with GLP-1 agonists may vary. Side effects may also vary based on the GLP-1 medication you take.
Remember the following considerations when thinking about using a GLP-1 and/or when talking to your healthcare provider about GLP-1 agonist medications.
You may not be a good candidate for GLP-1 agonists, depending on your health history. Certain health conditions, like kidney disease or a history of thyroid cancer, can affect whether or not you’re a good candidate for medication.
GLP-1 agonists can interact with other medications. Always inform your healthcare provider about all medications you’re currently taking, including supplements and over-the-counter medications.
There’s a risk of low blood sugar (hypoglycemia) when using GLP-1 agonists. Risk can increase if you take other medications that lower blood sugar. Hypoglycemia can cause symptoms like shakiness, sweating, headache, paleness, fatigue, and nausea. It’s important to treat hypoglycemia right away by increasing your blood glucose level. If you have diabetes, you should do this in accordance with your treatment plan. If you don’t have diabetes, you can help increase blood sugar with fast-acting carbs, like fruit juice.
You shouldn’t take GLP-1 agonist drugs during pregnancy. A study published in Frontiers in Endocrinology reported that these medications may increase the risk of pregnancy complications and birth defects.
Your body may have or develop allergies to GLP-1 agonists. Allergic reactions can also occur at the injection site. In rare cases, GLP-1 medications have caused anaphylaxis, a severe allergic reaction that can lead to shock and even death. If you experience symptoms of anaphylaxis, call 911 for emergency medical help.
Any of the medications included here should only be used for its FDA-approved use. While medications approved for the treatment of type 2 diabetes have led to weight loss, they are not approved for off-label use, such as weight loss. They are also not approved for people with BMIs outside of the approved ranges.
The use of some of these medications for weight loss, such as Ozempic for weight loss and Wegovy for weight loss outside of approved BMI ranges, has led to serious shortages. Shortages have led to repercussions from insurers and put people who need regular access to these medications at risk.
If you’re prescribed a weight loss medication after meeting qualifying conditions and/or get prior authorization if needed, your insurance should approve your using it and cover the cost outside of your co-pay and/or deductible depending on your plan.
But, if you’re prescribed the medication without a qualifying condition and/or BMI or if you don’t have insurance, you may find the costs of these medications too high. For instance, a two-month supply of Wegovy can cost upwards of $1,400 before insurance, according to drugs.com. Make sure your insurance will approve the medication if your doctor prescribes a GLP-1 agonist.
If your insurance doesn’t approve you for a GLP-1 medication, many drug manufacturers have savings or patient-assistance programs. Check the manufacturer’s website for details.
Always talk with your healthcare provider to determine if GLP-1 receptor agonist is right for you. Your provider can make sure weight loss pills are safe for you. They can also recommend the best prescription weight loss medication for your needs or an over-the-counter option.
Remember that most of the medications included here and most medically supervised weight loss plans include diet changes and exercise. Regular check-ups with your healthcare provider will let them track your progress. They can also adjust your treatment plan and medication as needed.
Other potential benefits and uses of GLP-1 agonist medications include the following.
A study originally published in the Journal of Experimental and Therapeutic Medicine found that some GLP-1 medications may lower the risk of heart disease. But it’s unknown if these benefits result from blood glucose control, a reduction in A1C levels, weight loss, or the drug itself.
Individuals on GLP-1 agonists have seen blood pressure and cholesterol improvements. Like the heart benefits, these benefits may be due to weight loss rather than the medication. Studies show that weight loss can lower total cholesterol levels in the body.
It can be overwhelming to start a weight-loss program. It’s easier to understand the right options, like prescription weight loss medications, diet, and exercise, with the help of a healthcare provider. A qualified healthcare professional will work with you to determine the best way for you to lose weight if needed.
On the Klarity platform, find a dedicated healthcare provider ready to help tailor a weight loss plan for your unique needs. Get started today.
The information provided in this article is for educational purposes only and should not be construed as medical advice. Always seek the guidance of a qualified healthcare professional with any questions or concerns you have regarding your health.
How we reviewed this article: This article goes through rigorous fact-checking by a team of medical reviewers. Reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the author.
Get free, credible health and wellness tips from Klarity
Subscribe to our blog for the latest insights and advice—totally free! No spam, and you can unsubscribe at any time.