There are multiple FDA-approved prescription medications for weight loss. They work in different ways. For example, some medications may help you feel less hungry or full sooner. These are phentermine, phentermine/topiramate (Qsymia), Liraglutide (Saxenda), and Semaglutide (Wegovy). Other medications may make it harder for your body to absorb fat from the foods you eat. This includes orlistat (Xenical, Alli).
Who can get the prescription medications for weight loss?
Prescription medications for weight loss are useful for people with health problems related to being overweight or obese. Health care professionals use BMI values to decide if you will benefit from these medications or not. You can be prescribed a medication to treat your overweight or obesity if you are an adult with
- a BMI of 30 or greater
- a BMI of 27 or greater, and you have weight-related health problems such as high blood pressure, type 2 diabetes, or high cholesterol
These prescription medications for weight loss aren’t for everyone with a high BMI. If you are overweight or have obesity, you might be able to lose weight with a healthy lifestyle program that changes your behaviors and improves your eating and physical activity habits. A healthy lifestyle program may also address other things that cause you to gain weight, such as eating triggers and not getting enough sleep.
Can prescription medications for weight loss replace physical activity and healthy eating habits as a way to lose weight?
Medications will not replace physical activity or healthy eating habits as a way to lose weight. Studies show that weight management medications work best when combined with a lifestyle program. Setup a virtual consult with our physician at Valley Forge Weight Management Center to learn about various treatment options for weight management that will work for you.
Weight management medications don’t replace physical activity and healthy eating habits.

How do prescription medications for weight loss help me?
When combined with changes to behavior, including healthy eating and increased physical activity, prescription medications for weight loss help some people lose weight and maintain weight loss. In most of the clinical trials for these prescription medications, on average, after 1 year, people who take prescription medications with a healthy lifestyle program lose 3% to 12% more of their starting body weight than those in the healthy lifestyle program who do not take medication.
Research shows that some people taking prescription weight management medications lose as much as 15% of their starting weight (especially with newer injectable prescription medications)[1]. Results vary by medication and by person.
Weight loss of 5% to 10% of your starting body weight may help improve your health by lowering blood sugar, blood pressure, and triglyceride levels. Losing weight also can improve some other health problems related to overweight and obesity, such as joint pain and sleep apnea. Most weight loss takes place within the first 6 months of starting the medication.
Weight loss of 5% to 10% of your starting body weight may help improve your health by lowering blood sugar, blood pressure, and triglyceride levels
Are there any concerns about using prescription medications for weight loss?
Like any other prescription medication, in some cases, the side effects of prescription medications for weight loss may outweigh the benefits. For this reason, never take a weight management medication only to improve the way you look. In the past, some weight management medications were linked to serious health problems and removed from U.S. markets.
Each medication has its own potential side effects, and they may vary in different people and how it acts on your body. Most side effects are mild and transient. They go away in a short time. Rarely, serious side effects can occur.
Tips for taking weight management medication
- Follow your health care professional’s instructions about weight management medications.
- Get your medication from a pharmacy or online distributor approved by your health care professional.
- Only take weight management medication as an adjunct to your healthy eating and physical activity program.
- Know the side effects and warnings before taking any medication.
- If you are not losing weight after 12 weeks on the full dose of your medication, ask your health care professional whether you should stop taking it.
- Talk with your health care professional about any other medications you are taking, including supplements and vitamins, when considering weight management medications.
- Never take weight management medications during pregnancy or if you are planning a pregnancy.
Your physician health coach at the Valley Forge Weight Management Center will review your medical conditions and recommend the most appropriate medication for you based on your needs. It is based on multiple factors, including:
- the likely benefits of weight loss
- the medication’s possible side effects
- your current health issues and other medications
- your family’s medical history
- cost
How long will I need to take prescription medications for weight loss?
It depends on whether the drug helps you lose weight and whether you experience any serious side effects from the medication. Most prescription medications for weight loss are approved by FDA for chronic weight management. If you have lost enough weight and are maintaining it without experiencing any serious side effects, you can stay on the medication indefinitely. If you do not lose at least 5% of your starting weight after 12 weeks on the full dose of your medications, it is advisable to stop the medication.
Your health care professional may also
- change your treatment plan or consider using a different weight management medication
- have you tried different lifestyle, physical activity, or eating programs
- change your other medications that might be causing weight gain
- refer you to a bariatric surgeon to see if weight-loss (bariatric) surgery might be an option for you
Because obesity is a chronic disease, it is important that you learn the lifestyle skills to continue to maintain the weight loss and your new eating and physical activity habits and other behaviors for years—or even a lifetime—to improve your health and maintain a healthier weight. At Valley Forge Weight Management Center, we emphasize lifestyle skills for weight loss.
What prescription medications for weight loss are currently approved by FDA?
Here are the prescription drugs approved by the FDA for weight loss. As of the publication date of this article, there are currently five FDA-approved drugs for long-term use —orlistat (Xenical, Alli), phentermine-topiramate (Qsymia), naltrexone-bupropion (Contrave), liraglutide (Saxenda), and semaglutide (Wegovy).
Some weight management medications that curb appetite are approved by the FDA for short-term use for up to 12 weeks. Although some health care professionals prescribe them for longer periods based on other studies and their experience with the drug. Patients should be monitored for long-term use of these drugs.
Never take weight management medications if you are pregnant. If you are planning to get pregnant, you should also avoid these medications, as some of them may harm the fetus.
Orlistat (Xenical, Alli)
Available in lower doses without a prescription (Alli). Approved for Adults and children ages 12 and older. Mechanism: Works in your gut to reduce the amount of fat your body absorbs from the food you eat. Common Side effects: diarrhea, gas, leakage of oily stools, stomach pain,
Warnings: Rare cases of severe liver injury have been reported, Avoid taking with cyclosporine, and Take a multivitamin pill daily to make sure you get enough of certain vitamins that your body may not absorb from the food you eat
Phentermine-topiramate (Qsymia)
Approved for Adults ages 18 and above.
Mechanism: A mix of two medications: phentermine, which lessens your appetite, and topiramate, which is used to treat seizures or migraine headaches. It may make you less hungry or feel full sooner
Common Side Effects: constipation, dizziness, dry mouth, taste changes, especially with carbonated beverages, tingling of your hands and feet, trouble sleeping
Warnings: Do not use if you have glaucoma or hyperthyroidism. Tell your health care professional if you have had a heart attack, stroke, abnormal heart rhythm, kidney disease, or mood problems. MAY LEAD TO BIRTH DEFECTS—DO NOT TAKE PHENTERMINE-TOPIRAMATE IF YOU ARE PREGNANT OR ARE PLANNING A PREGNANCY. Do not take if you are breastfeeding
Naltrexone-bupropion (Contrave)
Approved for Adults ages 18 and above
Mechanism: A mix of two medications: naltrexone, which is used to treat alcohol and drug dependence, and bupropion, which is used to treat depression or help people quit smoking. May make you feel less hungry or full sooner
Common Side Effects: Constipation, diarrhea, dizziness, dry mouth, headache, increased blood pressure, increased heart rate, insomnia, liver damage, nausea, vomiting
Warnings: Do not use if you have uncontrolled high blood pressure, seizures, or a history of anorexia or bulimia nervosa. Do not use if you are dependent on opioid pain medications or are withdrawing from drugs or alcohol. Do not use if you are taking bupropion (Wellbutrin, Zyban). MAY INCREASE SUICIDAL THOUGHTS OR ACTIONS
Liraglutide (Saxenda)
Given daily by injection. Approved for Adults and children ages 12 years and older
Mechanism: Mimics a hormone called glucagon-like peptide-1 (GLP-1) that targets areas of the brain that regulate appetite and food intake. At a lower dose under a different name, Victoza, this drug was FDA-approved to treat type 2 diabetes
Common Side Effects: nausea, diarrhea, constipation, abdominal pain, headache, increased heart rate.
Warnings: May increase the chance of developing pancreatitis. Has been found to cause a rare type of thyroid tumor in animals.
Semaglutide (Wegovy)
Given weekly by injection. Approved for Adults
Mechanism: Mimics a hormone called glucagon-like peptide-1 (GLP-1) that targets areas of the brain that regulate appetite and food intake. Under different names and dosages, this drug was FDA-approved to treat type 2 diabetes as an injectable medication (Ozempic) and as an oral pill (Rybelsus)
Common Side Effects: nausea, diarrhea, vomiting, constipation, abdominal (stomach) pain, headache
fatigue
Warnings: Do not use in combination with other semaglutide-containing products, other GLP-1 receptor agonists, or other products intended for weight loss, including prescription drugs, over-the-counter drugs, or herbal products. May increase the chance of developing pancreatitis. Has been found to cause a rare type of thyroid tumor in animals
Other medications that curb your desire to eat include: phentermine, benzphetamine, diethylpropion, phendimetrazine
Approved for Adults. Phentermine is FDA approved for adolescents ages 16 and above for short-term use.
Mechanism: Increases chemicals in your brain to make you feel you are not hungry or that you are full. Note: FDA-approved only for short-term use—up to 12 weeks
Common Side Effects: dry mouth, constipation, difficulty sleeping, dizziness, feeling nervous, feeling restless, headache, raised blood pressure, increased heart rate
Warnings: Do not use if you have heart disease, uncontrolled high blood pressure, hyperthyroidism, or glaucoma. Tell your health care professional if you have severe anxiety or other mental health problems.
Will insurance cover the cost of weight management medication?
The insurance coverage is limited for prescription medications for weight loss. Some, but not all, insurance plans cover medications that treat overweight and obesity. Contact your insurance provider to find out if your plan covers these medications. At Valley Forge Weight Management Center, we consider the cost factors also before suggesting the best medication option for you.