When combined with changes to behavior, including eating and physical activity habits, prescription medications may help some people lose weight. On average, people who take prescription medications as part of a lifestyle program lose between 3 and 9 percent more of their starting body weight than people in a lifestyle program who do not take medication.

Weight loss of 5 to 10 percent of your starting body weight may help improve your health by lowering blood sugar, blood pressure, and triglycerides. Losing weight also can improve some other health problems related to overweight and obesity, such as joint pain or sleep apnea.

Most weight loss takes place within the first 6 months of starting the medication.

Concerns with using prescription meds to lose weight?

Experts are concerned that, in some cases, the side effects of prescription medications to treat overweight and obesity may outweigh the benefits. In the past, some weight-loss medications were linked to serious health problems. For example, the FDA recalled fenfluramine and dexfenfluramine (part of the "fen-phen" combination) in 1997 because of concerns related to heart valve problems.

Tips for Taking Weight-loss Medication

• Follow your doctor's instructions about weight-loss medications.
• Take weight-loss medication to support your healthy eating and physical activity program.
• Read the labels. Know the side effects and warnings for taking any medication.
• Ask your doctor if you should stop taking your medication if you are not losing weight after 12 weeks.
• Discuss other medications, including supplements and vitamins, you are taking with your doctor when considering weight-loss medications.
• Avoid taking weight-loss medications during pregnancy or if you are planning a pregnancy.

How long will one need to take weight-loss medication?

How long you will need to take weight-loss medication depends on whether the drug helps you lose and maintain weight and whether you have any side effects. If you have lost enough weight to improve your health and are not having serious side effects, your doctor may advise that you stay on the medication indefinitely. If you do not lose at least 5 percent of your starting weight after 12 weeks on the full dose of your medication, your doctor will probably advise you to stop taking it. He or she may change your treatment plan or consider using a different weight-loss medication. Your doctor also may have you try different lifestyle, physical activity, or eating programs; change your other medications that cause weight gain; or refer you to a bariatric surgeon to see if weight-loss surgery might be an option for you.

Because obesity is a chronic condition, you may need to continue changes to your eating and physical activity habits and other behaviors for years - or even a lifetime - to improve your health and maintain a healthy weight.

Medications are available to treat overweight and obesity are provided in the next blog post.