If your BMI is higher than 25, you have an increased risk of several health conditions, including heart disease, stroke, diabetes, and severe COVID-19. Losing as little as 5–10% of your weight can significantly improve your health. Weight loss medications, in addition to diet, exercise, and lifestyle modifications, are appropriate for some people to help with their weight loss goals.
It's important to keep in mind that BMI does not account for factors like sex, body composition, and more. Additionally, research to support BMI as an assessment tool lacks racial and ethnic diversity.
Many weight loss pills are contraindicated for certain health conditions or medications. For example, people who are pregnant or breastfeeding should not take weight loss pills. Other common contraindications include uncontrolled high blood pressure and MAO inhibitors.
Review the prescribing information for any weight loss pill you are considering, and be sure to tell your healthcare provider about any health conditions you have as well as any medications you are taking. Sharing this information with them can help them determine the best weight loss pill for you.
How Well Do Weight Loss Pills Work?
Unfortunately, there is no magic pill to cure obesity. However, weight loss pills can help make a weight loss journey more successful, especially when combined with diet and exercise. And, the strongest weight loss pills have been tested for efficacy and safety in clinical trials.
These FDA-approved weight loss pills mainly work by suppressing your appetite. Some do so by activating parts of your brain involved in appetite regulation—such as naltrexone/bupropion, phentermine/topiramate, and phentermine—leading to fewer cravings and less hunger. Others, such as orlistat, work by blocking how much fat you absorb from food, so you absorb fewer calories overall.
How much weight you lose on weight loss pills can depend on the medication and other lifestyle changes you make. Improving your diet and increasing your physical activity may lead to more weight loss. In general, people tend to lose between 3%–9% of their body weight after one year of taking weight loss pills, in combination with lifestyle changes.
How Long Do I Need to Take Weight Loss Pills?
How long you need to continue taking weight loss pills depends on several factors and will vary from person to person. Depending on the side effects you experience and the success of your weight loss, your healthcare provider may need to adjust your dosage.
If your weight loss is successful and you don't experience negative side effects, your health care provider may recommend taking weight loss pills long-term to help you keep the weight off. If you take your medication as prescribed and aren't seeing results, your health care provider may prescribe you a different weight loss pill.
That said, the Food and Drug Administration has approved certain weight loss pills for short-term vs. long-term use. As mentioned above, phentermine is only FDA-approved for short-term use (up to 12 weeks). For long-term weight management, the FDA has approved three weight loss pills: phentermine/topiramate (Qsymia), naltrexone/bupropion (Contrave), and orlistat (Xenical, Alli).
Other Medications That May Help With Weight Loss
The drugs mentioned above are the ones that carry FDA approval. However, other drugs may be used "off-label" to help with weight loss. Off-label simply means that a drug is being used for a condition that it was not originally approved to treat.
Take metformin, for example. Metformin is approved to treat type 2 diabetes but is used off-label to treat prediabetes based on data from the Diabetes Prevention Program, which showed a reduction in diabetes incidence by 30%. Nowadays, metformin is also used off-label to treat other conditions, like obesity, where it can cause up to 7% weight loss.
Antidepressants, drugs used to treat depression, are another class of medications that may help people lose weight. Bupropion, one of the drugs in the FDA-approved weight loss medicine Contrave, is an antidepressant that may aid weight loss.
Other Weight Loss Treatments
Other options are available if prescription weight loss medications aren't right for you.
Weight loss surgery
While surgery is the most invasive form of weight management, many of these procedures have been shown to help with weight loss, including:
- Gastric banding: An inflatable band is placed around the stomach to create a smaller pouch, effectively reducing how much food can be eaten and making patients feel fuller faster.
- Sleeve gastrectomy: Most of the stomach is removed in this procedure, leaving patients with a smaller stomach that takes less food to feel full. It has the added benefit of affecting the gut hormones that play a role in hunger, feeling full, and blood sugar control.
- Gastric bypass: Also called Roux-en-Y gastric bypass, is a complicated surgery that reduces the size of the stomach and rearranges the small intestine to decrease calorie absorption. It can also affect gut hormones.
Weight loss surgery is an effective option for managing weight, but it does come with a risk of side effects and potential complications, such as nausea, vomiting, heartburn, abdominal pain, and infections. Some of these procedures can increase your risk for nutrient deficiencies like vitamin B12, iron, and folate deficiencies.
Will I Gain Weight Back if I Stop Weight Loss Medication?
Unfortunately, even the strongest weight loss pills only work as long as you take them—when you stop them, you will likely gain weight back. Think of medications as another tool to manage your weight–just like diet and exercise. If you stop exercising, you are likely to gain weight back; similarly, stopping the medication can result in weight regain as well.
Do Weight Loss Pills Replace Diet and Exercise?
Weight loss pills shouldn't replace diet and exercise. Weight loss drugs should be part of a comprehensive treatment plan that includes lifestyle modifications, like diet and exercise, counseling, and behavioral interventions. Adding lifestyle changes may also help you minimize weight regain if you stop the weight loss pills.
People taking weight loss pills along with lifestyle modifications lose, on average, 7–10% of their initial weight after one year. These compounding effects may improve your risk of multiple health problems like type 2 diabetes and high blood pressure.
Weight loss pills may be the added boost you need to help you lose weight. However, they're not for everyone. Talk to your health care provider about prescription medications for weight management to determine if any are right for you.
