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Andres Acosta, M.D. Ph.D., is an obesity researcher at Mayo Clinic in Rochester, Minnesota and co-author of The Mayo Clinic Diet: Weight-Loss Medications Edition. Here, he answers common questions about prescription obesity medicines.
Q: Who can take prescription obesity medicines?
A: Prescription weight-loss medicines may be an option if your body mass index (BMI) is in the overweight or obese category. These medicines are approved for people who have a BMI greater than 30 or a BMI greater than 27 coupled with a serious obesity-related medical condition, such as diabetes or high blood pressure.
Q: How do obesity drugs work?
A: Medicines approved by the Food and Drug Administration (FDA) for the treatment of obesity work primarily by reducing appetite and increasing feelings of fullness.
Q: What can I expect after taking a weight-loss medication?
A: During the first few weeks of taking a weight-loss drug, a rapid drop in weight is typical. This is likely due to a significant decrease in calorie intake, coupled with a loss of water weight.
When you take obesity medicines, you typically don’t feel like eating as much. When you consume fewer calories, your body releases stored energy in the form of glycogen, a type of sugar stored in your muscles and liver. Because glycogen is partly water, when your body burns it for energy you also lose water and, thus, weight. This effect is temporary.
Incidentally, this initial period also is when side effects are most bothersome.
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Q: Is it dangerous to lose weight very quickly?
A: Loss of muscle tissue can make it harder to maintain weight loss long term. In addition, rapid weight loss also can result in nutrient deficiencies and side effects such as hair loss.
Although it’s OK to see rapid weight loss initially, the goal is to eventually move to a slower, more stable process — 1 to 2 pounds a week. This is generally better because, with this type of weight reduction, you tend to lose more fat.
Q: How long will I need to take a weight-loss drug?
A: Ideally, you’ll want to pose this question to your healthcare team. As you work with the team to weigh the pros and cons of staying on your medicine long term, keep the following in mind:
Effectiveness: How long you take a weight-loss drug depends on whether your body responds to it. If you’ve lost adequate weight and aren’t bothered by side effects, your healthcare team may suggest that you stay on the drug even after you’ve reached your goal weight. On the other hand, if you haven’t lost at least 5% of your body weight after taking the full dose of a drug for 3 to 6 months, your care team may discontinue or change your treatment. Together, you may decide to try a different drug to see if it works better or stop using these drugs altogether.
Tolerance: If side effects interfere with your daily life and activities, tell your healthcare team. Your care team might be able to adjust the medication’s dosage to reduce your symptoms. Another option is to try a different weight-loss drug to see if it’s effective and if you tolerate it better.
Administration: Many weight-loss medicines require daily or weekly injections. This delivery method can be challenging if you have needle phobia or injection site redness, swelling or itching. Contact your healthcare team to ensure you have thorough training on proper injection techniques. Make sure to change your injection sites regularly and use mild, nonirritating cleansers to help keep the areas clean.
Cost: Weight-loss drugs can be costly and are not always covered by insurance. Some pharmaceutical companies offer patient assistance programs or copay assistance programs to help reduce the cost of the medicines. Your healthcare team also may be able to prescribe different drugs or therapies that are more affordable or have better insurance coverage.
Health: It may be necessary to stop the medicine if you have a change in health status. That’s why it’s essential to have ongoing conversations with your healthcare team to assess your prescription. Remember that a lifestyle intervention program, like the Mayo Clinic Diet, can continue to support your weight-loss journey regardless of whether you’re taking weight-loss medicine.
Q: What should I do when I stop taking obesity medicine?
A: Your lifestyle becomes even more critical once you go off your medicine. Research shows that 9 out of 10 people who keep a healthy weight exercise for around an hour daily. In addition to doing cardiovascular exercise, include at least two strength training sessions weekly. Keeping muscle is vital to maintaining a healthy weight because muscle burns more calories.
This article originally appeared in the Mayo Clinic Health Letter.
Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission.
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