Few medicines have drawn as much attention as the newer weight-loss drugs. Semaglutide, sold for weight management as Wegovy, and tirzepatide, sold as Zepbound, work on hormones involved in appetite and blood sugar. They are effective, they are not right for everyone, and they work best as part of a longer plan.

This article is general information to help you prepare for a conversation with your doctor. It is not a recommendation to start or avoid any medicine.

What these medicines are

They are not the only option. NIDDK notes that the FDA has approved six drugs for long-term weight management: orlistat, phentermine-topiramate, naltrexone-bupropion, liraglutide, semaglutide and tirzepatide. Each works differently and suits different people.

GLP-1 receptor agonists mimic a gut hormone that helps regulate appetite, slows stomach emptying and affects insulin release. Tirzepatide acts on GLP-1 and a second hormone receptor, GIP. Both are given as weekly injections for weight management. NIDDK keeps an overview of prescription medications to treat overweight and obesity, including who they are approved for.

When the FDA approved Zepbound in 2023, it was for adults with obesity, defined as a BMI of 30 or higher, or overweight, a BMI of 27 or higher, with at least one weight-related condition such as high blood pressure, type 2 diabetes or high cholesterol, used together with a reduced-calorie diet and more physical activity.

What the trials showed

Side effects and cautions

Nausea, diarrhea, vomiting and constipation are the most common side effects. In the trials, they were usually mild to moderate and eased over time, most often during dose increases. Some people stop because of them.

These medicines also carry warnings and situations where they should not be used, which your doctor and pharmacist will go through. Tell every doctor, dentist and surgeon you see that you take one, especially before a procedure with sedation.

For older adults, the aim is to lose fat while keeping as much muscle and bone as possible, which is why strength training and enough protein belong in the plan. See strength training after 50 and body composition vs. BMI.

What happens when you stop

These are generally long-term treatments. In an extension of the STEP 1 trial, people who stopped semaglutide regained about two-thirds of the weight they had lost within a year, and improvements in blood pressure and other measures moved back toward where they started. NIDDK addresses the same question in its overview of weight medications. NIDDK also notes that some insurance plans do not cover weight management medicines, and suggests contacting your insurer to find out. Check before you start, since stopping for cost reasons means losing much of the benefit.

A word about compounded and online versions

The FDA has warned about unapproved GLP-1 drugs used for weight loss, including compounded and counterfeit products. It notes that unapproved versions do not undergo FDA review for safety, effectiveness and quality, and advises getting a prescription from your doctor and filling it at a state-licensed pharmacy.

Questions to bring to your doctor

  1. Does my health picture, including blood pressure, blood sugar, cholesterol, kidney function and joints, make weight treatment worthwhile?
  2. How would a medicine interact with what I already take?
  3. What would I do to protect muscle and bone while losing weight?
  4. How would we judge whether it is working, and for how long would I take it?
  5. What is the plan if side effects or cost become a problem?

Obesity is a chronic condition, as our earlier article on why obesity is a disease explains, and it deserves the same careful approach as any other. At Legacy Medical, Dr. Shtern reviews every prescription you take and keeps track of how a new one is going, with many follow-ups by video. To talk it through in person, book a complimentary meet and greet.

This article is general information, not advice for your situation. Members can call the office with questions about their own care.