Weight-loss drugs: Can a prescription help you lose weight?

Weight-loss drugs can improve your health, if used in combination with a healthy diet and regular exercise. Find out if you could benefit from taking these medications.

Weight-loss drugs may sound like a dieter's dream. But they aren't a good choice for everyone who's overweight. In fact, many doctors reserve them for people with weight-related health problems.

It's best to lose weight through a healthy diet and regular exercise. But if you're among those who struggle to lose weight and the excess weight has produced medical problems, weight-loss drugs may be able to help you.

Are you a candidate?

Prescription weight-loss drugs aren't intended for people who just want to lose a few pounds for cosmetic reasons. They're generally reserved for people who are unable to achieve or maintain a healthy weight through diet and exercise, and often have health problems as a result.

Your doctor may consider you a candidate for medication treatment if these criteria apply:

Other methods of weight loss haven't worked for you.
Your body mass index (BMI) is greater than 27 and you have medical complications of obesity, such as diabetes, high blood pressure or sleep apnea.
Your BMI is greater than 30.

Common weight-loss drugs

Two prescription drugs have been approved by the Food and Drug Administration (FDA) for long-term weight loss. These drugs work in different ways and cause different side effects.

Drug	Typical initial dosage	Estimated cost (30-day supply)	Common side effects
Sibutramine (Meridia)	5 to 15 milligrams (mg) once a day	$112 to $213	Increased blood pressure, headache, dry mouth, constipation and insomnia
Orlistat (Xenical)	120 mg three times a day	$132 to $380	Frequent oily bowel movements, diarrhea, bloating and abdominal pain

Though not prescribed as often, several medications, such as phentermine (Adipex-P), are approved for short-term use. These drugs suppress appetite, but haven't been the subject of many long-term studies. When used for a short time — generally less than 12 weeks — the medications usually lead to only temporary weight loss. Side effects of these drugs include dry mouth, nausea, vomiting, dizziness and lightheadedness.

Alli is the reduced-strength version of orlistat (Xenical). It's approved for over-the-counter sale to overweight adults 18 years and older. Alli is meant to be used in conjunction with a low-calorie, low-fat diet and regular exercise. Alli can help you lose weight, but the weight loss likely won't be great — perhaps just a few pounds more than you would lose with diet and exercise alone. Common side effects include diarrhea and gas with oily spotting. You can limit the side effects by eating a low-fat diet.

Effectiveness: Modest but can improve health

Combining weight-loss drugs with a low-calorie diet and regular exercise can help you lose more weight than can either drugs or lifestyle changes alone. Combining all three — medication, fewer calories and more activity — can help you lose anywhere from 5 percent to 10 percent of your total body weight within a year.

This may not seem like many pounds lost, but even modest weight loss has a significant benefit to your health. Losing just a small percentage of your weight can decrease:

Blood pressure
Blood triglyceride levels
Blood glucose levels
Insulin levels

Weight-loss drugs don't replace the need for changes in your eating habits or activity level. They mainly improve your chances of achieving clinically significant weight loss — the amount of weight loss that has a positive impact on your health.

Drug safety: Still largely unknown

If you're among those who can benefit from a weight-loss drug, you'll likely need to take it indefinitely. When you stop drug treatment, however, much or all of the lost weight generally returns. The dilemma with taking the drugs indefinitely is that the most common weight-loss drugs are so new that possible long-term effects are unknown.

Sibutramine can cause a small increase in blood pressure that, for some people, may warrant discontinuing the drug. This drug isn't recommended for people with uncontrolled high blood pressure, heart disease, irregular heartbeat or a history of stroke.

Orlistat decreases the absorption of certain fat-soluble vitamins — for example, vitamins A, D and E. If you're taking this drug, your doctor will recommend that you take a daily vitamin supplement to prevent potential nutrient deficiencies.

Factors to consider

You and your doctor need to carefully evaluate the potential benefits of taking a drug and weigh them against the possible long-term risks. Your doctor will also consider your health history, the possible side effects and the potential interaction of weight-loss drugs with other medications you're taking.

Keep in mind that some health insurance plans don't cover weight-loss prescription drugs. And some companies may require prior authorization before covering the expense. If you're unsure of your prescription coverage, contact your health insurance provider.

These medications can help you with weight maintenance, especially if you continue exercising regularly. But keeping off the pounds once you've lost them is an ongoing concern. And despite your efforts, you might still regain the weight.

As you consider weight-loss drugs, make sure that you make every effort to exercise, change your eating habits and adjust any other lifestyle factors that have contributed to your excess weight. Weight-loss drugs aren't the easy answer to weight loss, but they can be a useful tool to help you make the necessary diet and lifestyle changes.