Is Obesity Medication for Weight Loss Right for Me?

Losing weight on your own can sometimes seem like a never-ending struggle. If you have a lot of weight to lose and lifestyle changes haven’t worked, medication for weight loss may be an option.

Prescription obesity medications treat obesity. According to the National Institutes of Health (NIH), the disease affects more than 2 in 5 American adults.

“Obesity is a chronic, debilitating disease. Excess weight can lead to serious illness, including diabetes, heart disease, and high blood pressure,” says Caroline M. Apovian, MD, a Mass General Brigham obesity medicine specialist and co-director of the Brigham and Women’s Hospital Center for Weight Management and Wellness.

Dr. Apovian and Fatima Cody Stanford, MD, MPH, MPH, MBA, a Mass General Brigham obesity medicine specialist, recommend that patients take obesity medications only under a doctor's care.

Who qualifies for weight loss medication (obesity medication)?

“Medication may help if you have overweight or obesity and you aren’t making enough progress with diet and exercise alone,” says Dr. Stanford, who cares for patients at the Massachusetts General Hospital Weight Center.

Doctors use a measure of weight relative to height, called body mass index (BMI), as a guideline to determine who may benefit from obesity medication. High BMI levels are associated with increased body fat and greater risks for future health problems.

BMI for obesity medication

Generally, your doctor may prescribe medication if you are an adult who has:

• Obesity, a BMI of 30 or greater
• Overweight, a BMI of 27 or greater and associated health problems such as diabetes or high blood pressure

While doctors use BMI to diagnose overweight and obesity, it has some limitations. In early 2025, Dr. Stanford was a co-author of the Lancet Diabetes and Endocrinology Commission, which recommended new criteria for obesity that include body (anthropometric) measurements alongside BMI for persons with severe obesity. Body measurements help doctors understand where fat is stored in the body, which can carry health risks even if someone doesn’t have a high BMI.

“BMI is a guideline, but everyone has different needs. That’s why it’s important to work with a physician who will review your personal health history to determine if medication is right for you,” says Dr. Apovian.

Medication shouldn’t be used as a quick fix for someone who wants to lose 10 or 15 pounds before a class reunion or fit into the perfect dress.

“This is not for aesthetic goals. Medication is used to treat the chronic disease of obesity and diseases caused by obesity,” stresses Dr. Stanford. She adds that these medications are not appropriate for people who are pregnant or planning a pregnancy.

Can medication treat obesity in children?

Prescription drugs for weight loss may be suitable for children age 12 and older with overweight and obesity and, in rare instances, for children as young as 6.

What can I take to lose weight?

Some obesity drugs target the brain to decrease appetite, while others affect the gut to control how the body absorbs fat from foods or make you feel fuller longer. They help with weight loss, which can improve overall health by reducing cholesterol, blood sugar, and blood pressure.

Common prescription medications for weight loss

Prescription drugs approved by the U.S. Food and Drug Administration (FDA), commonly used to treat people with overweight and obesity are:

• Liraglutide (Saxenda®)
• Naltrexone-bupropion (Contrave®)
• Orlistat (Alli®, Xenical®)
• Phentermine-topiramate (Qsymia®)
• Semaglutide (Wegovy®)
• Tirzepatide (Zepbound®)

Setmelanotide for obesity caused by genetic conditions

Another drug, setmelanotide (IMCIVREE®), is used to treat obesity in people who have three rare genetic conditions confirmed by genetic testing:

• Proopiomelanocortin (POMC) deficiency
• Proprotein convertase subtilisin/kexin type 1 (PCSK1) deficiency
• Leptin receptor (LEPR) deficiency

The weight you can lose depends on your medication, how your body responds to it, and a commitment to healthy eating and exercise. Studies show the newest drugs—semaglutide and tirzepatide—may help you lose up to 20% of body weight. However, some people lose much less.

How to use prescription medications for weight loss

Depending on the drug and your doctor’s advice, you’ll have to take pills or give yourself injections in the upper arms, stomach, or thighs.

Your doctor will work with you to develop a weight management plan that includes medication tailored to your specific needs. Your plan may also include a healthy diet with lots of produce and lean proteins, and regular cardio and strength training exercises.

“Weight management treatment should include access to obesity medicine specialists, dietitians, physical therapists, and psychologists to address your medical, physical, and emotional needs,” says Dr. Apovian.

You may be prescribed one medication or a combination of medications. Some people respond better to certain options.

Obesity medication before and after weight loss surgery

If you choose to have bariatric surgery, you may also use obesity medication before and after surgery to give you the best chance at long-term success.

“People who opt for medication combined with bariatric surgery have the most success because it’s a combination of the best anti-obesity therapies available,” Dr. Stanford adds.

Side effects of weight loss injections and pills

Serious side effects of weight loss drugs are rare.

“Nausea is the most common side effect, affecting close to half of people who take anti-obesity medication. It typically gets better over time as the dose increases and your body acclimates to the medication,” says Dr. Stanford. “If side effects are too unbearable, you may need to try a different medication.”

Depending on the option you take, you may also experience:

• Abdominal symptoms, such as abdominal pain, changes in stool, constipation, gas, heartburn, liver damage, and vomiting
• Dizziness and fatigue
• Dry mouth and taste changes
• Hair loss
• Headache
• Increased blood pressure or heart rate
• Runny nose or sore throat
• Tingling of hands and feet, or neuropathy

Long-term use of medication for weight management

It may sound easy to lose weight with medication, but it’s not. Once you reach your goal weight, you need to continue taking obesity medication, eating a healthy diet, and exercising to maintain the loss.

Dr. Stanford likens weight loss medication to wearing deodorant. “As soon as you forget it, you notice,” she adds. “Many of our patients have been under our care for a decade or longer.”

That’s why it’s important to find an obesity specialist you can work well with to support you and manage your care, Dr. Apovian says. “Similar to taking medication to control other diseases like high blood pressure, it’s a long-term commitment for better health.”