When diet and exercise are not enough for weight loss
12/21/2023 by Ramona DeJesus, M.D.
There are times when diet and exercise are not enough to achieve weight loss and additional help in the form of medicines and surgery is needed. Here are some things to consider when thinking of weight-loss medications.
Who should take weight-loss medications?
Your body mass index (BMI), which is a measurement of your weight relative to your height, is used to define overweight and obesity. Adults with a BMI between 25 and 30 are considered overweight and those with a BMI of 30 or greater are considered obese. The Food and Drug Administration (FDA) has approved the use of weight-loss medications in adults who:
- Have a BMI of 30 or greater.
- Have a BMI between 27 and 29.9 and have weight-related medical conditions such as diabetes, high cholesterol, heart disease or high blood pressure.
The first step in deciding if a weight-loss medication is right for you is to review your blood work and medical history with your healthcare clinician. Remember that although medications can help achieve success with weight loss, they can also be harmful and lead to serious side effects if not prescribed appropriately. They also do not replace diet and exercise, which alone can result in about 5% weight loss.
How do weight-loss medications work?
Weight-loss medications work by reducing your appetite or changing the way you digest food. They help achieve a better hormonal balance between the stomach and brain to change the way your body and mind respond to food.
How do I pick the right medication?
There is no one best option. It's more about finding one that fits your lifestyle and health profile. You may have other health conditions that may benefit from a certain medication. The goal is to lose at least 5% to 10% of your starting body weight, which will significantly improve overall health.
How long do I take weight-loss medications?
Most weight loss typically takes place within six months of starting weight-loss medications. Some people achieve success around this time, while others don't. It's important to follow up with your healthcare clinician often, especially when you hit roadblocks. As a rule of thumb, if you do not lose at least 5% of your starting weight after 12 weeks on the full dosage of your medication, your healthcare clinician may recommend that you stop taking it and switch to a different medication.
Many people gain back some of the weight that they lose when they stop taking weight-loss medication, so it's important to continue practicing healthy lifestyle habits to help limit weight gain.
What are the available medicines for weight loss?
Weight-loss medications are no magic pill, but if used in the right setting, they may help you lead a healthier life. Pregnant women should never take weight-loss medications. Women who are planning to get pregnant should also avoid these medications, as some may harm a fetus.
These medications have been approved by the FDA for weight loss in adults and children ages 12 years and older, except for Contrave, which is indicated only for adults. Another medication, Setmelanotide (Imcivree) is approved only for children ages 6 years and older who have rare genetic disorders causing obesity.
- Orlistat (Xenical): This medication works by reducing the amount of fat your body absorbs from the foods you eat. A lower-dose version, Alli, is available without a prescription in many countries, including the U.S. Common side effects include diarrhea, oily stools, gas and stomach cramps.
- Naltrexone-bupropion (Contrave): This medication is a mix of naltrexone, which is used to treat alcohol and drug dependence, and bupropion, which is used to treat depression or help people quit smoking. This medication makes you feel less hungry or full sooner. Side effects are constipation, diarrhea, dry mouth, headache, increased blood pressure, increased heart rate, insomnia and liver damage. It should not be used if you have uncontrolled high blood pressure, a history of seizure or eating disorders, or are dependent on opioid pain medication.
- Phentermine (Lomaira, Adipex-P): This medication, which curbs your appetite, is FDA-approved for short-term use only — up to 12 weeks. Side effects include increased heart rate and blood pressure, insomnia, constipation, dry mouth and nervousness.
- Phentermine/topiramate (Qsymia): This medication is a mix of phentermine, which lessens your appetite, and topiramate, which is used to treat seizures or migraine headaches. This medication works by making you less hungry or feel full sooner. Side effects include racing heartbeat, constipation, dry mouth, dizziness, trouble sleeping, tingling and a sudden decrease in vision.
- Liraglutide (Saxenda): This medication, also used to treat diabetes, mimics a hormone called glucagon-like peptide 1 (GLP-1) which targets areas of the brain that regulate appetite and food intake. It may make you feel less hungry or full sooner. It is given as a daily injection. Side effects include constipation or diarrhea, nausea, abdominal pain and rapid heart rate. It also may increase the chances of developing pancreatitis.
- Semaglutide (Wegovy): Approved in June 2021, this medication also mimics GLP-1 and is given as a weekly injection. Common side effects are similar to liraglutide and include nausea, diarrhea and stomach pain. It should not be given to people with a personal or family history of certain thyroid cancers or a rare condition called Multiple Endocrine Neoplasia Syndrome type 2 (MEN 2).
- Tirzepatide (Zepbound): Just approved by the FDA in November 2023, this medication is also part of the medication class that mimics GLP-1 and helps reduce food intake and appetite. However, it also imitates a second hormone called GIP, which along with reducing appetite, may improve how the body breaks down sugar and fat. It is administered by injection once a week. Side effects include abdominal pain, constipation, diarrhea and indigestion.
- Setmelanotide (Imcivree): This medication is FDA-approved only for children 6 years and older who have specific rare genetic conditions causing obesity confirmed by genetic testing.
It's important to understand the risks, benefits and limitations of these medications. Side effects may be bothersome. Long-term safety data are limited and they can be expensive. Be sure to consult your primary care clinician before starting any weight-loss medication.
Ramona DeJesus, M.D., is a general internist in Primary Care in Rochester and Kasson's Division of Community Internal Medicine, Geriatrics and Palliative Care. She completed her medical degree at the University of Florida and completed her residency at Mayo Clinic in Rochester. She is board-certified in internal and obesity medicine. Her interests include chronic disease management in primary care and population health management of high-risk patients.