Questions patients may have about weight-loss drugs

Obesity continues to be a significant global health concern, affecting millions of individuals worldwide. Recognizing the urgency to combat this pervasive issue, medical advancements have paved the way for the development of various weight-loss drugs or anti-obesity medications. These pharmaceutical interventions aim to assist patients in achieving their weight loss goals by supplementing lifestyle changes and promoting sustainable results.

But, as with any medication, questions and concerns naturally arise among patients considering or prescribed these anti-obesity weight-loss drugs. It is crucial to address these inquiries comprehensively, ensuring patients have accurate information and a clear understanding of the potential benefits and risks associated with such medications.

Here are some questions patients may have about weight-loss drugs or anti-obesity medications, along with the answers that physicians should be ready to share.

Some are oral medications while others are self-administered once-a-week injections. Prescription weight loss medications work in different ways to treat overweight and obesity. For example, some anti-obesity medications may help you feel less hungry or full sooner.

On the other hand, medications may also make it harder for your body to absorb fat from the foods you eat, according to the National Institutes of Diabetes and Digestive and Kidney Diseases (NIDDK). Anti-obesity medications may also target cravings, food preferences and thoughts about food.

The first generation of weight-loss drugs were developed in the 1930s through the 1960s. These agents were stimulants—such as dinitrophenol and methamphetamine—and are only approved for short-term use for weight-loss because some are amphetamine-based, which is a cause of concern of addiction.

With the withdrawal of fenfluramine—part of Fen-Phen—and dexfenfluramine as well as a better understanding of obesity, a second generation of weight loss medications were developed. These targeted the central regions of the brain as well as the digestive system, including Contrave (naltrexone HCI and bupropion HCI) and Qsymia (Phentermine and topiramate), according to the Cleveland Clinic.

But now there are newer weight loss drugs that have turned their attention to gut hormones—such as glucagon-like peptide-1 (GLP-1)—which are involved in appetite and weight regulation. Many of these medications are used to treat obesity and type 2 diabetes. The newest anti-obesity medication approved by the U.S. Food and Drug Administration (FDA) is semaglutide, which is known as Wegovy. This is a higher dose of the same medication, Ozempic, which was approved four years earlier for type 2 diabetes. Saxenda (liraglutide) is also a GLP-1 receptor agonist and is the same class as semaglutide.

While this class of GLP-1 receptor agonist medications has been around for almost 20 years for the treatment of type 2 diabetes, longer-acting once-a-week medications appear to be more effective in treating obesity and lowering blood glucose.

Another medication that has been making headlines is tirzepatide, which is sold under the brand name Mounjaro. Use of tirzepatide resulted in more than a 20% weight reduction in those with obesity. But this has not been approved by the FDA for use as an anti-obesity medication. It is approved for the treatment of type 2 diabetes, though, and the drug trial’s sponsor is working towards FDA approval for weight loss, according to Yale Medicine.

Additionally, a new anti-obesity medication that has completed a phase 2 trial is from Eli Lilly. The phase 2 trial was published in the New England Journal of Medicine and showed that patients with obesity lost an average of 58 pounds at the end of a 48-week treatment course. This weight-loss drug from Eli Lilly is an injectable called retatrutide. It has not been approved yet.

Working together with a physician is the best way to determine if a medication to treat obesity is the best option for each patient. When choosing a medication, it is important to keep a few things in mind. It is important to look at the likely benefits of weight loss, the medication’s possible side effects, a patient’s current health issues and other medications being taken, their family’s medical history and the cost.

Weight loss medications are meant to help people who have health problems related to overweight and obesity. While an imperfect clinical measure, physicians typically use body mass index (BMI) in addition to other measures of health risk—such as waist circumference, genetic and metabolic factors, or body composition—to determine whether someone will benefit from weight management medications.

These medications may be prescribed to treat overweight or obesity in adults with a BMI of 30 or greater, or with a BMI of 27 or greater if you have weight-related health problems such as high blood pressure or type 2 diabetes.

But weight-loss drugs are not for everyone. For example, patients who are trying to get pregnant, are pregnant or are breastfeeding should not take weight-loss drugs.

Most weight management medications that have been approved by the FDA are for adults only. But Orlistat (Xenical and Alli) and liraglutide (Saxenda) are two prescription medications that are approved by the FDA for children 12 or older, according to NIDDK.

Setmelanotide—also known as Imcivree—is another anti-obesity medication that is approved by the FDA for children 6 or older who have rare genetic disorders that can cause obesity.

While anti-obesity medications will help a person lose weight without exercising and dieting, long-term health benefits come from incorporating lifestyle changes at the same time. That is because the combination of anti-obesity medicine and lifestyle changes leads to greater weight loss than lifestyle changes alone.

The American Association of Clinical Endocrinologists and American College of Endocrinology guidelines recommend that medications in conjunction with lifestyle modifications be considered for all patients with a BMI of at least 27 if lifestyle change alone fails to halt weight gain. 

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As with any medication, there may be some side effects with anti-obesity drugs. The most common side effects are mild and can include nausea, constipation and diarrhea. These side effects typically lessen over time.

There are also serious side effects that can happen but are rare. That is why it is important to work with a physician to determine the best treatment option.

The length of time you need to take an anti-obesity drug depends on whether the medication helps with losing weight. For those who have lost enough weight to improve their health and have not experienced any serious side effects, physicians might suggest taking the weight-loss drug long term.

If a patient has not lost at least 5% of their body weight after taking the full dose of the medication for three to six months, physicians will likely adjust the treatment plan. This would include switching to a different weight-loss drug, according to the Mayo Clinic.

Additionally, with obesity the regulation of a person’s body set point is dysfunctional. While you can restrict calories for years, your body is always trying to get back to that dysfunctional set point. That is why anti-obesity medications are valuable in correcting an issue with the fat regulatory system, says the Cleveland Clinic.

Unfortunately, anti-obesity medications can be expensive, and they are not always covered by insurance. Patients should review their insurance company medication formulary to find out if their plan covers these medications.

After a year of taking anti-obesity medication, it could mean a loss of total body weight of 3% to 12% more than if you were doing lifestyle changes alone. It may not seem like a lot but losing 5% to 10% of total body weight—and keeping it off—can have important health benefits. For example, it can lower blood pressure and blood glucose levels as well as levels of fat in the blood called triglycerides, says the Mayo Clinic.

It is important to note that anti-obesity medications do not replace physical activity or healthy eating habits as a way to lose weight. Research shows that weight management medications work best when they are combined with a lifestyle change program. Physicians and other health professionals can help provide further guidance on what lifestyle changes to make.

When a patient stops taking weight-loss drugs, they will likely gain back some of the weight they lost while on the medication. Fortunately, though, practicing healthy lifestyle habits may help to limit any weight gain should you go off an anti-obesity medication.

This requires a team-based care approach. While consulting a physician is key, there are also other important members of the team who can help with weight loss and further support. Working with physicians should be dieticians, behavioral health specialists, pharmacists and other health professionals who can help to support the optimum outcome of the medications recommended. This also includes lifestyle modification as well as determining coverage for the weight-loss drugs and selection of the best anti-obesity medication for the patient.

Another healthy way for patients to lose weight and make appropriate lifestyle changes is through participation in a National Diabetes Prevention Program (National DPP) lifestyle change program. The AMA’s Diabetes Prevention Guide supports physicians, care teams and health care organizations in defining and implementing evidence-based diabetes prevention strategies.