If you're like most people, you have probably put on excess pounds over the years. Losing even a little bit of that weight can improve your health — especially if you have type 2 diabetes. The combination of less weight and more exercise often leads to lower blood sugar. Weight loss also reduces your risk for heart disease. Plus, it gives you energy and helps you feel your best. A sensible diet and regular physical activity are still the keys to lasting weight loss. But when these changes alone aren’t enough, weight-loss medications sometimes help. Thanks to new weight-loss drugs, you have more options to choose from today. But keep in mind: Although medications help some people slim down, they’re not for everyone, and they can have side effects. Your doctor can help you decide if medication might be right for you. Here’s what you need to know about weight-loss medications. How Weight-Loss Drugs Work Prescription weight-loss drugs work in a variety of ways: Belviq (lorcaserin), which was approved by the FDA in 2012 for treating obesity, affects a brain chemical called serotonin. This helps suppress your appetite and make you feel full after eating less food. In studies conducted as part of the FDA approval process, nearly half of patients who began taking Belviq had lost at least 5% of their initial body weight a year later. Qsymia (phentermine-topiramate), also approved by the FDA in 2012, helps reduce your appetite and curb your desire to eat. In studies, after patients had taken Qsymia for a year, over 60% had lost at least 5% of their body weight. Xenical (orlistat) blocks the digestion of about one-third of the fat you eat. After a year or two on Xenical, patients often lose 5 to 7 pounds. A lower-strength version of this drug is sold over the counter as Alli. Saxenda (liraglutide), approved by the FDA in 2015, helps you feel satiated, reduces hunger sensations, and decreases appetite. A clinical trial showed that 62% of people on liraglutide lost at least 5% of their body weight. All these drugs can be taken long term. That’s a benefit, because some people need long-term help to avoid regaining weight once they’ve lost it. Important Factors to Consider In general, weight-loss drugs are for people who have a body mass index (BMI) of 30 or above. But when you have a weight-related health problem, such as type 2 diabetes, the threshold is lowered to a BMI of 27 or above. Women who are or may become pregnant shouldn’t take these medications. Like all medications, weight-loss drugs can cause side effects: Belviq may cause headaches, dizziness, tiredness, nausea, constipation, dry mouth, and coughing. It shouldn’t be taken with SSRI and MAOI antidepressants. The combination may lead to a rare but serious condition called serotonin syndrome. Symptoms of serotonin syndrome include high fever, confusion, and stiff muscles. Qsymia may cause tingling hands and feet, dizziness, taste changes, dry mouth, trouble sleeping, and constipation. It’s especially important not to take this drug while pregnant, because it may cause birth defects. Xenical may cause stomach pain, gas, diarrhea, and leaking of oily stools. Side effects may be worse if you eat a high-fat diet. Because this drug interferes with the absorption of some vitamins, you should take a multivitamin with it. Saxenda may cause nausea, diarrhea, constipation, vomiting, low blood sugar (hypoglycemia) and decreased appetite. Saxenda can also raise heart rate and should be discontinued in people who experience a prolonged increase in their resting heart rate. In some rare cases, patients reported serious side effects like pancreatitis, gallbladder disease, renal impairment, and suicidal thoughts. Weight-loss drugs aren’t effective for everyone. If you aren’t losing weight after three months, talk with your doctor. It may be time to try a different approach. Short-Term Appetite Suppressants Several other medications may be prescribed as short-term appetite suppressants. The most common one in the United States is phentermine (Adipex-P, Oby-Cap, Suprenza, T-Diet, Zantryl). Others include benzphetamine (Didrex), diethylpropion (Tenuate, Tenuate Dospan) and phendimetrazine (Adipost, Bontril, Melfiat). Such medications are only FDA-approved for up to 12 weeks of use, though some doctors prescribe them for longer. Common side effects include dizziness, headache, nervousness, restlessness, dry mouth, trouble sleeping, stomach problems, diarrhea, and constipation. Bottom line: If you’ve improved your diet and increased your physical activity, but you’re still having trouble losing weight, ask your doctor whether a weight-loss drug might help. These pills won’t do all the work — you’ll still have to make healthy lifestyle choices. But they may boost the benefits of lifestyle changes and help you shed those stubborn pounds. Key Takeaways Losing weight and exercising more can lower your blood sugar. When eating sensibly and exercising aren’t enough to help you lose weight, weight-loss medications might be an option. Belviq, Qsymia, Xenical, and Saxenda are prescription drugs used for treating obesity. They are for people who have a body mass index (BMI) of 30 or above — or 27 or above if you have a weight-related health problem such as type 2 diabetes. Short-term appetite suppressants are another option for weight loss. They are FDA-approved for up to 12 weeks of use, but some doctors prescribe them for longer. Weight-loss drugs do not work for everyone, and they have side effects. Talk with your doctor to determine what is best for you.