Millions of Americans struggle with obesity. To combat rising overweight and obesity rates across the country, healthcare providers are turning to prescription medication to aid weight management. Weight loss medications help patients lose weight and keep it off.

There are so many weight loss drugs on the market. Learn more about prescription weight loss medications and the best treatment options.

Who is eligible to use weight-loss medication?

A licensed healthcare provider must prescribe prescription weight loss medications. Weight loss drug prescriptions are at the discretion of the prescribing provider. In some cases, providers may hold off prescribing medication until it’s clear that lifestyle changes don’t effectively help a patient lose weight. In other cases, a provider may prescribe medication to a patient who doesn’t fit the criteria above.

The Food and Drug Administration (FDA) recommends these drugs for people who:

• Have a body mass index over 30 (obesity)
  
• Have overweight (a BMI over 25) with an obesity-related health condition
  

Obesity can cause weight-related health conditions.

These health conditions include:

• Heart disease
  
• Strokes
  
• High blood pressure (hypertension)
  
• Type 2 diabetes
  
• Cancer (especially cancers of the internal organs)
  
• Sleep apnea (potentially life-threatening breathing problems when sleeping)
  
• Gallbladder disease
  
• Liver problems
  
• Osteoarthritis (damage to the joints)
  
• Gout
  
  

Prescription weight loss medication is used in conjunction with healthy lifestyle changes, such as a reduced-calorie diet and regular physical activity. Weight loss drugs are not nearly as effective if taken without changing exercise and eating habits.

FDA-approved weight loss medications

The FDA has approved several prescription weight loss drugs for use as part of a complete weight loss treatment plan. Oral medication (pills) help patients lose weight. However, a new crop of injectable medications are stronger and may lead to more significant weight loss.

A review of clinical studies shows that phentermine-topiramate led to the most weight loss in a year.

1. Phentermine-topiramate (Qsymia): This is a combination of a weight-loss drug (Phentermine) and an anticonvulsant (topiramate). On average, patients who took Qsymia for a year (along with healthy lifestyle changes) lost an average of 11% of their body weight

2. Orlistat (Xenical): Orlistat belongs to a classification of medications known as lipase inhibitors. Prescription-strength orlistat is available under the brand name Xenical. A lower-strength version of Xenical is available over the counter under the brand name Alli. On average, patients who used Xenical for a year (with lifestyle changes) lost 10% of their body weight.
3. Bupropion-naltrexone (Contrave): Contrave controls your appetite, cravings, and metabolism. In clinical trials, most patients who took Contrave for a year lost 5% or more of their body weight.

4. Phentermine (Adipex-P, Lomaira): When prescribed alone, phentermine is approved for short-term use and is also considered a controlled substance. It helps control appetite and is usually only prescribed for up to 12 weeks.

Injectable weight loss drugs are potent weight management aids. They are usually taken once a week. Based on clinical trials, Zepbound led to the most weight loss of all injectable weight loss drugs.

1. Tirzepatide (Zepbound): Zepbound is a brand-name prescription weight loss medication. It belongs to a class of drugs known as glucagon-like peptide-1 (GLP-1) receptor agonists. GLP-1 receptor agonists control blood sugar and hunger levels, which help patients control the amount of calories they eat during the day. In clinical trials, patients lost an average of 20.9% (about 49 lbs) of their body weight after 36 weeks of Zepbound treatment.
2. Semaglutide (Wegovy): Wegovy is another GLP-1 medication officially approved for weight loss. In clinical trials, patients lost an average of 12.4% (about 28 lbs) of their body weight after 68 weeks of Wegovy treatment.
3. Liraglutide (Saxenda): Saxenda is a GLP-1 medication approved for weight loss. In clinical trials, patients lost an average of 9.2% (about 21 lbs) of their original body weight.

4. Setmelanotide (Imcivree): Setmelanotide is administered via injection to patients with obesity due to relatively rare genetic medical conditions. It belongs to a class of medications known as melanocortin 4 (MC4) receptor agonists. These drugs work by reducing appetite and boosting resting metabolism.

Prescription weight loss drugs vary in their effect on the body. The prescribed drug will depend on your condition, health history, and other medications and supplements you are taking.

Do weight loss drugs cause side effects?

If a healthcare professional prescribes a weight-loss medication, they believe that the benefits outweigh the potential side effects. However, weight loss drugs can cause some side effects.

Specific side effects will vary depending on the patient and drug.

The most common side effects of weight loss medication include:

• Nausea
  
• Upset stomach
  
• Abdominal pain
  
• Constipation or diarrhea
  
• Dry mouth
  
• Increased heart rate
  
• Headaches
  
• Dizziness
  
  

Before starting treatment, discuss potential side effects with your provider and inform them about any medications and supplements you are taking. Before starting treatment, you should also talk about your medical history and any conditions you are managing.

Be sure to tell your provider about conditions like:

• High cholesterol
  
• High blood pressure
  
• Heart disease
  
• Diabetes (type 1 or 2)
  
• Glaucoma
  
• Liver disease
  
• Kidney disease
  
• Thyroid disorders
  
• Thyroid tumors
  
• Pancreatitis
  
• Eating disorders
  
• Mental health conditions
  
  

Weight loss medication is generally not recommended for women who are pregnant, are planning to become pregnant, or are currently breastfeeding.

Weight loss medication should be used with lifestyle changes

Weight loss drugs are most effective when used along with healthy lifestyle changes.

These include:

• A healthy, reduced-calorie diet
  
• Regular physical activity
  
  

Lifestyle changes help with weight loss goals while also helping to prevent serious health conditions such as:

• High blood pressure
  
• Type 2 diabetes
  
• High cholesterol
  
• Heart disease
  
  

Any prescription drug you are given to help with weight loss should be taken in addition to–not instead of–these healthy practices as a part of a sustainable treatment plan.

How long do I need to take weight loss drugs?

Most prescription drugs listed above are approved for long-term use. If you lose enough weight and do not experience any serious side effects, you may be directed to continue taking the medication.

Research shows that patients who take prescription weight loss drugs lose about 10% of their initial body weight when combining medicine with a healthy diet and regular exercise.

These results vary from person to person. If you have not lost 5% of your body weight after 3-6 months of taking weight loss medication, your doctor may adjust your dosage or prescribe a different form of treatment.

Start your weight loss journey with Sesame’s online weight loss program. During your first visit, you can discuss your weight loss goals and the best type of prescription weight loss medication for you. Providers will prescribe medication if appropriate and can provide ongoing support with unlimited messaging.

Sources:

• (2023). Prescription Medications to Treat Overweight & Obesity. NIH.
  
• Abbasi J. (2023). FDA Green-Lights Tirzepatide, Marketed as Zepbound, for Chronic Weight Management. JAMA.
  
• Bansal AB, Al Khalili Y. (2022). Orlistat. NIH.
  
• Lonneman, D. J., Jr, Rey, J. A., & McKee, B. D. (2013). Phentermine/Topiramate extended-release capsules (qsymia) for weight loss. P & T : a peer-reviewed journal for formulary management.
  
• Márquez-Cruz, M., Kammar-García, A., Huerta-Cruz, J. C., Carrasco-Portugal, M. D. C., Barranco-Garduño, L. M., Rodríguez-Silverio, J., Rocha González, H. I., & Reyes-García, J. G. (2021). Three- and six-month efficacy and safety of phentermine in a Mexican obese population. International journal of clinical pharmacology and therapeutics.
  
• Pi-Sunyer, X., Astrup, A., Fujioka, K., Greenway, F., Halpern, A., Krempf, M., Lau, D. C., le Roux, C. W., Violante Ortiz, R., Jensen, C. B., Wilding, J. P., & SCALE Obesity and Prediabetes NN8022-1839 Study Group (2015). A Randomized, Controlled Trial of 3.0 mg of Liraglutide in Weight Management. The New England journal of medicine.
  
• Sherman, M. M., Ungureanu, S., & Rey, J. A. (2016). Naltrexone/Bupropion ER (Contrave): Newly Approved Treatment Option for Chronic Weight Management in Obese Adults. P & T : a peer-reviewed journal for formulary management.
  
• Singh, G., Krauthamer, M., & Bjalme-Evans, M. (2022). Wegovy (semaglutide): a new weight loss drug for chronic weight management. Journal of investigative medicine : the official publication of the American Federation for Clinical Research.
  
• Trapp, C. M., & Censani, M. (2023). Setmelanotide: a promising advancement for pediatric patients with rare forms of genetic obesity. Current opinion in endocrinology, diabetes, and obesity.