When it comes to rising levels of obesity in the United States, there's finally a glimmer of good news. In addition to three drugs now commonly used to treat the overweight and obese, three more weight-loss prescription drugs are in the works. Many researchers say safe and effective weight-loss medications can save lives and a ton of money by curbing the incidence of weight-related diseases such as stroke, heart disease, diabetes and some cancers.

The three prescription drugs presently used to treat obesity include sibutramine (Meridia), which increases satiety; phentermine, which suppresses appetite; and orlistat (Xenical), which prevents some dietary fat from being absorbed by the intestine. Orlistat is sold in a lower dose over-the-counter, like Alli. The Food and Drug Administration is reviewing safety information regarding reports of liver-related adverse events in patients taking orlistat.

Like the three well-known drugs above, the new drugs are intended either for people who are obese, which is considered to be 30 or more pounds over a healthy weight, or for overweight patients who have risk factors like high blood pressure. A quick review of the three new drugs:

• Qnexa (Vivus). Preliminary studies show it may reduce appetite and simultaneously increase the sense of fullness.
• Lorcaserin (Arena Pharmaceuticals). It works on brain chemistry to induce a sense of fullness; patients lost an average of 17 pounds, but many experienced headaches.
• Contrave (Orexigen). It fights food cravings and improves the ability to control eating. Common side effects are nausea and constipation.

Originally reported in USA Today, it's important to note that obesity medication must paired with major lifestyle changes, such as regular exercise, like walking, physician support and ongoing research. Some patients in the newest drugs trials had improvements in blood pressure, cholesterol, triglycerides and blood sugar control. The three new drug companies must submit their applications to the FDA and go through a rigorous review process. Even if the medications receive government approval, it'll be at least a year until they're available.

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